Keywords

1 Introduction

Consumers’ tendency to manifest polyvalent behaviour, in conditions of constant change and evolution, enhanced by innovations in information and communication technology, brings new and diverse challenges for retailers in terms of maximising customer experience. Retailers need to reinvent themselves continuously and to customise their value proposition to each individual consumer. While product assortment, pricing and service policy are generally considered essential elements of a retailer’s toolkit (marketing mix), the other elements appear as secondary, supporting elements. However, in the face of increased competitive pressure and the changing habits of the digital consumer, they are equally important in attracting and retaining customers.

Retailers constantly change or renew product assortments, adjust prices, rethink or restructure the environmental space in the store, reconsider the distribution and communication policy and the commercial services offered. Alongside innovation, an equally significant role is played by the customisation of these elements. To achieve maximum levels of customer satisfaction, it is useful for retailers to think about the purchase experience from an experiential marketing perspective. This involves identifying the contact points and, for each of them, the factors that activate all five senses of shoppers to create the intended feelings, thoughts and actions (Frazer and Stiehler 2014). Shopping must be an entertaining, exciting and emotionally engaging experience.

The omni-channel business model is oriented towards augmenting consumers’ perceived shopping value. It has a powerful effect on the shopping experience, making it a unique, individual, customised process which favours acquisition. Customers can use any of the available distribution and communication channels, which are all integrated, at any moment of the buying process. The two worlds, online and offline, are merged to provide the ultimate experience. Physical store visits are enhanced using mobile technologies and electronic information kiosks, while online channels benefit from order pickup in stores and direct contact with the products.

Since the literature on the subject is fragmented, this paper provides an integrative view of this topic, focusing on aspects of the omni-channel concept and the strategic implications for its implementation. The next section presents our methods and the evolution to omni-channel retailing from its precursors. Subsequently, we review the omni-channel concept and its retailing strategies, identifying inconsistencies in its implementation. Finally, we present a research framework to address current shortcomings.

2 Method

The literature review process began with a search of relevant articles for the omni-channel theme. First, we searched through the main databases, Emerald Management Journals 200, Science Direct and Scopus, using ‘omni-channel’, ‘omnichannel’ or ‘omni retailing’ as keywords, and identified a set of 53 primary articles published between January 2013 and February 2018. We then sought and added relevant pieces of literature referring to omni-channel or omni-retailing that did not appear in the database searches for “omni-channel”. This led to a total of approximately 136 articles. Among these, a total of 96 articles were relevant to the topic of the current literature review, defining the three related concepts and/or detailing omni-channel strategy implementation (Table 1).

Table 1 The primary set of articles on omni-channel (February 2018)
Full size table

2.1 From Multi-channel Through Cross-Channel to Omni-Channel…

Distribution strategy is an important source of competitive advantage for any retailer. It is defined on the one hand by the number and types of sales channels, and on the other by the means and level of interconnection between them (Chatterjee 2010). While most retailers start with one distribution channel, be it store, non-store or electronic, an increasing number have gradually added multiple channels to the initial one. The multi-channel retail approach blossomed in the 1990s, with the addition of other physical store formats, online or mobile channels to existing physical stores, direct mailing, catalogues, television-based selling channels or call centres (Grewal et al. 2004). Online retailers have also added physical showrooms or pickup points. Hence, the number of contact points between retailers and customers has increased. The trend is continuously expanding worldwide due to consumer acceptance of technological innovations such as the Internet, smartphones, social networks, and virtual assistance (De Faultrier et al. 2014).

Nowadays, the channels used by retailers to communicate with customers or distribute products may be physical, with tangible formats (sales force, physical stores or kiosks, catalogues, direct selling) or virtual/electronic, using telecommunication, information and multimedia technology (direct mail, call centres, websites, kiosks, interactive television, mobile applications or mobile internet, gaming consoles, networked appliances, automated retailing, mass communication and social media) (Verhoef et al. 2015). Consumers can select the distribution channel most suited to them from the perspective of proximity, convenience, store environment, prices, staff courtesy (Bieberstein 2015), product and information availability, and speed of delivery (Yee and Heutger 2015). This facilitates their access to products, which in turn contributes to increased frequency of visits, a higher volume of purchases, increased satisfaction and loyalty, etc.

Retailers approach the different channels which they operate in distinct ways, varying the level of integration from none to complete. Depending on the level of integration of channels, the strategy carries distinct names, from multi-channel to cross-channel and omni-channel retailing (Picot-Coupey et al. 2016).

In the initial phase of channel diversification, many retailers operate multiple independent channels, often in competition with each other. Even though they try to optimise consumer experience in each channel, this might vary across channels, as might product information, pricing and level of service (DHL Trend Research 2015). When a retailer simultaneously operates several distinct channels that are not integrated, the strategy is called multi-channel retailing (Wallace et al. 2004). Customers can choose the channel they want for an acquisition and cannot switch to another channel during the buying process. The emphasis is placed on the channel and on improving customer experience as it pertains to the channel, not the brand.

There are many definitions of multi-channel retailing in the literature of 15–20 years ago. One of the first definitions is that of Stone et al. (2002), which states that multi-channel retailing is ‘a distribution strategy to serve customers using more than one selling channel or medium, such as the internet, television and retail outlets’. No other conditions need to be met to be considered multi-channel strategy. Neslin et al. (2006) define multi-channel as the ‘design, deployment, coordination and evaluation of channels to enhance customer value through effective customer acquisition, retention, and development’. The authors highlight the importance of channels as customer interaction points. The definition describes multi-channel as a seamless customer interface and experience across channels. In fact, this describes omni-channel strategy (Beck and Rygl 2015). The same confusion is present in the definition of Lewis et al. (2014, 44), who see multi-channel retailing as a model in which retailers use a combination of two or more integrated channels to sell products and services to consumers”.

A different definition is that of Chatterjee (2010, 10), in whose opinion multi-channel retailing consists of ‘operating multiple channels as independent entities’. Anderson et al. (2010) correctly use the term ‘multi-channel retailer’ to describe a retailer who sells merchandise through more than one channel, where the customer cannot trigger channel interaction and the retailer does not control channel integration. A multi-channel structure is simply defined by Zhang et al. (2010, 167) as ‘all activities involved in the sale of merchandise or services to the consumer through more than one channel’, that are developed separately. Such independently operated channels are aimed at certain target customer segments. The same idea may be found in the definition by Frazer and Stiehler (2014, 655): ‘different channels of shopping are still being operated in isolation’. This approach is found in many articles and books (Zentes et al. 2017); thus, it may be concluded that a consensus regarding this concept has been reached.

The addition of an increasing number of interaction channels leads to complications in the coordination effort. Channel integration becomes necessary in order to provide the same level of service to customers and to better respond to consumer need for continuous interaction throughout the purchase process. Integration is defined by Chiu et al. (2011, 271) as ‘the mutual support of or interchangeability between online and offline channels’. Recently, retailers have tended to integrate selling channels. However, there are retailers who do not integrate channels because it is easier to manage them independently. Others avoid doing this because, for instance, they want to charge different prices on different channels, or the channels are targeted at various consumer segments or markets (Zentes et al. 2017).

Cross-channel retailing implies some degree of channel integration compared with multi-channel strategy. The concept is defined as ‘integrated multiple channels, allowing cross-channel movements of products, money and information’ (Chatterjee 2010, 10). Customers can switch retail channels at any stage of the shopping process: information search, product availability, purchasing, delivery arrangements, returns, etc. (Zentes et al. 2017). For example, they can search for information using their mobile application, then order a product online and pick it up in a store, or search for it online, buy it in a store and have it delivered to their home. According to Beck and Rygl (2015), there are two configurations of cross-channel retailing: one where customers can trigger partial interaction and/or some or all channels are partially integrated, and another in which the customer can trigger full interaction and/or at least two channels—but not all—are fully integrated.

Even though there has been much scientific research in the field of multi-channel retailing, cross-channel and omni-channel retailing are still new research themes, which is why authors sometimes confuse them (Beck and Rygl 2015; Mosquera et al. 2017; Reis et al. 2017). For instance, Cao (2014, 70) seems to consider cross and omni-channel retailing to be similar, ‘integrated multichannel strategies’, while Chopra (2016, 135) defines omni-channel as being similar to multi-channel, with ‘the use of a variety of channels to interact with customers and fulfil their orders’. However, there seems to be a consensus in many papers regarding the meaning. Multi-channel retailing refers to the use of various selling channels that can only be used in parallel, and which are managed independently. Customers cannot move from one channel to another. Cross-channel displays a certain level of integration, with customers being able to change channels at various stages of the information and transaction process. Omni-channel represents the full integration of channels, and the ability of customers to simultaneously use all the channels at any given step of the purchasing process (Piotrowicz and Cuthbertson 2014; Mosquera et al. 2017). Verhoef et al. (2015) clearly specify the differences between omni-channel and cross-channel retailing. Omni-channel retailing has more channels; customer touchpoints are also included; the borders between channels are blurred; the focus is on the customer brand experience, and everything is redesigned around this philosophy.

2.2 The Concept of Omni-Channel Retailing

Omni-channel retailing is the natural and logical evolution or reconfiguration from multi- and cross-channel retailing (Gibson et al. 2015). It displays the highest level of integration and takes place among all channels. In this type of business model, clients use channels simultaneously, in parallel, in a continuous way and can migrate between them at any moment of the purchasing process, depending on their personal preferences (Zentes et al. 2017), because the retail system is designed as a holistic entity.

This strategy has been created as a response to changes in consumer expectations. Since they can access the Internet through multiple digital devices, at any time, customers expect to be able to use an ever-increasing number of offline, online and mobile channels and touchpoints interchangeably and simultaneously while shopping (Verhoef et al. 2015; Cummins et al. 2016). They also need immediate access to information, a personalised shopping experience and speedy delivery (DHL Trend Research 2015).

The term ‘omni-channel’ originated among business practitioners. According to Lazaris and Vrechopolous (2014), the first use of the term was in IDC’s Global Retail Insights research unit reports; whereas Parker and Hand (2009) and Ortis and Casoli (2009) suggested that the omni-channel shopper is an evolution of the multi-channel consumer, who uses all channels simultaneously instead of in parallel.

While there are many definitions of the concept in both business reports and academic papers, variations in the understanding of the concept still exist. There is even a lack of agreement over whether there is consensus on the meaning or not. Huré et al. (2017) observe that, even though consent has emerged among academics regarding the definition of omni-channel, its features are still unclear.

We analysed the articles by means of content analysis (Kolbe and Burnett 1991) to structure the definitions, capture the main characteristics of omni-channel retailing to better understand the term, and identify two main characteristics of the concept. This analysis led us to develop three categories: (a) the retailer’s point of view i.e. the integration of the selling channels; (b) the consumer’s point of view i.e. achieving a seamless shopping experience; and (c) a combination of both these points of view.

2.2.1 Integrated Channels from the Retailer’s Perspective

Rigby (2011, 1) was the first to present the term ‘omni-channel retailing’ in academic literature. He defined the concept as ‘an integrated sales experience that melds the advantages of physical stores with the information-rich experience of online shopping’. This definition mentions not only the integration of retail channels during the purchasing process, but the customer experience derived from this as well. His definition was later adopted by numerous other researchers such as Frazer and Stiehler (2014), Lazaris and Vrechopolous (2014), Lazaris et al. (2014), Piotrowicz and Cuthbertson (2014), Picot-Coupey et al. (2016), Reis et al. (2017), and Yumurtaci et al. (2017).

Fairchild (2014, 447) defines omni-channel commerce as ‘combining traditional commerce with online commerce by integrating processes in a harmonious and complementary way throughout the organisational and IT chain and includ[ing] external logistics partners in these processes’. The author underlines the idea that channels need to be integrated, extending the definition to include external partners as well. Although the emphasis in the definition is on retailers’ internal processes, the researcher underlines that the final aim of this type of commerce is to satisfy demand everywhere, at any given time. Bieberstein (2015) claims that whenever the distribution channels and social media contact points of a retailer are interconnected and have symbiosis and synergy between them, there is omni-channel retailing. Ailawadi and Farris (2017) do not explicitly provide a definition of omni-channel, but rather a description of how they understand it. Here, we find the same idea, that omni-channel employs multiple distribution and communication channels, whose activities are integrated within and across channels to better suit consumers’ shopping needs. The definition of Eriksson et al. (2017, 764) states that ‘physical stores (bricks-and-mortar) and online channels are fully integrated. The retailer is facing the customer with one common interface for all sales channels and inventories and order fulfilment are merged across the network’. Zentes et al. (2017, 96) also assert that omni-channel retailing ‘involves total channel integration. Customers can shop via all retail channels in parallel, because the omni-channel system is designed as a holistic entity, ideally with every touchpoint of every retail channel available’.

In business literature, the most prestigious consultancy companies agree upon the integration of channels within the omni-channel strategy. Thus, Carroll and Guzmán (2013) have a very similar approach: ‘a synchronised operating model in which all of the company’s channels are aligned and present a single face to the customer, along with one consistent way of doing business’. A report written by DHL Trend Research (2015, 4) underlines the idea of convergence with the aim of providing personalised customer experience: ‘it requires the previously separate sales channels to converge into a single seamless channel of orchestrated product flow—this flow must be designed to deliver not just products but also the highly personalised shopping experience customers have come to expect’. PWC (2017, 4) describes the strategy as one where ‘the role of the store and online channels are complementary and are managed in an integrated and seamless manner’.

All these definitions emphasise the need to integrate distribution and communication channels within an omni-channel retail strategy. Apart from this, they all agree that the final goal of the strategy is to provide superior customer service.

2.2.2 Seamless Shopping Experience for Customers

What is different here is that authors consider the seamless experience of customers, and not the integration of channels, to be the main aspect of omni-channel strategy. This does not mean that integration is excluded; however it is little discussed.

Departing from Rigbyʼs (2011) definition, Kozlenkova et al. (2015, 593) define omni-channels as providing a ‘seamless retail experience across all end-user channels, making products available via multiple channel formats’. The idea conveyed by the definition is the same, namely that the omni-channel system ensures maximum information availability, visibility and consistency across multiple channels (Piotrowicz and Cuthbertson 2014; Saghiri et al. 2017). Gonzales-Lafaysse and Lapassouse-Madrid (2016, 573) have built on this idea and define omni-channel retailing as ‘interacting with consumers through disparate channels so as to provide a single seamless omni-channel experience’.

Kamel and Kay (2011) and Frazer and Stiehler (2014) reason that a true omni-channel experience is based on the ‘desire to serve the customer however, whenever and wherever they wish to purchase merchandise (and return it too)’. Kireyev et al. (2014, 29) understand the term omni-channel to mean ‘a similar if not identical experience across the many different channels they may use to interact with the retailer’. Bell et al. (2015) describe omni-channel as allowing the customer the freedom to inform and fulfil their order using the channel that they find most suitable. However, this definition could also apply to multi- and cross-channel retailing, because it does not state clearly enough whether the channels can be used simultaneously.

In the business literature, Deloitte (2015) considers omni-channel to mean an interactive and personalised customer experience with the brand, achieved using all possible touchpoints or channels.

2.2.3 Integrated Channels Offer a Seamless Shopping Experience

Some authors rally around this view and include both aspects in their definitions. One of the most cited definitions of omni-channel is that of Brynjolfsson et al. (2013, 4): ‘as the retailing industry evolves toward a seamless “omnichannel retailing” experience, the distinctions between physical and online will vanish, turning the world into a showroom without walls’. Departing from the papers of Rigby (2011) and Brynjolfsson et al. (2013), Picot-Coupey et al. (2016, 340) define omni-channel management as ‘a strategy that manages channels as intermingled touchpoints to allow consumers to live a seamless experience within a brand eco-system’. The same idea, expressed as ‘unified cross-channel shopping experience’ can be found in the earlier works of Pelet and Lecat (2014, 188) and Wisner and Wisner (2014, 14)—the ‘ability to have a continuous experience across brands, across formats, and across devices that is completely customised’ and optimised. Piotrowicz and Cuthbertson (2014) add that the experience is with the brand, not with the channel. Bernon et al. (2016, 586) define omni-channel in a very similar way as ‘a seamless approach to retailing that offers a single and unified shopping experience across all retail channel formats’.

Verhoef et al. (2015, 176) stress that in omni-channel retailing, the different channels and touchpoints are used ‘constantly, interchangeably, and simultaneously by both customers and firms to facilitate the customers’ retail experience’. The authors define omni-channel management as the ‘synergetic management of the numerous available channels and customer touchpoints, in such a way that the customer experience across channels and the performance over channels is optimised’. The idea conveyed by the definition is that the different channels interact with each other and can be used simultaneously. They add that it is ‘virtually impossible for retailers to control this use’ of channels by customers (Verhoef et al. 2015, 175). The definition has been accepted and cited by numerous academics, such as Fornari et al. (2016), Picot-Coupey et al. (2016), Hosseini et al. (2017), Kembro and Norrman (2017), Manser Payne et al. (2017), Mosquera et al. (2017), Saghiri et al. (2017), and Abdulkader et al. (2018). Cummins et al. (2016, 5) expand the definition provided by Verhoef et al. (2015), combining it with the vision of Piotrowicz and Cuthbertson (2014) to underline the end goal of achieving a unified brand experience for the customer through the integration of all retailing channels. The new definition is the ‘synergetic integration of customer touchpoints and communication opportunities for the purpose of creating a unified brand experience regardless of channel, platform or stage in the selling process’.

Levy et al. (2013, 67) introduced the term omni-retailing as ‘a coordinated multi-channel offering that provides a seamless experience when using all of the retailer’s shopping channels’. Beck and Rygl (2015) consider omni-channel a selling strategy that includes all channels, is widespread, and allows consumers to fully interact with all channels. Regarding channel integration from the retailers’ viewpoint, they can be partially or fully integrated. The level of integration between channels leads to the division of omni-channel strategy into two types. For Juaneda-Ayensa et al. (2016, 1), the omni-channel strategy is ‘a form of retailing that, by enabling real interaction, allows customers to shop across channels anywhere and at any time, thereby providing them with a unique, complete, and seamless shopping experience that breaks down the barriers between channels’. Juaneda-Ayensa et al. (2016) consider omni-channel only as the latter category of those defined by Beck and Rygl (2015). Thus, they consider omni-channel to be the fully integrated channels of a retailer. The same idea is underlined by Wollenburg et al. (2016), Hosseini et al. (2017), Kembro and Norrman (2017), Mosquera et al. (2017) and Reis et al. (2017), who consider that, in omni-channel retailing ‘neither the customer nor the retailer distinguishes between channels anymore’.

Chopra (2016) understands omni-channel retailing to be the symbiotic approach of clients, aimed at enhancing their experience, emotions and fulfilment of their needs and expectations, regardless of the chosen distribution channel. Based on a literature review, Mosquera et al. (2017) create an integrative framework that encompasses the main characteristics of omni-channel. These are: (1) the employment of several channels; (2) blurred barriers between them and integrated data across channels, and (3) the final goal of providing consumers with a holistic shopping experience. Thamm et al. (2016) also speak about the connection between channels using a central infrastructure, and about a unified shopping experience. Based on the literature, Ailawadi and Farris (2017), Beck and Rygl (2015), Verhoef et al. (2015), and Huré et al. (2017, 315) conclude that omni-channel could be referred to as ‘the complete alignment of the different channels and touchpoints, resulting in an optimal-brand customer experience’.

By analysing these papers and their underlying discussion of omni-channel, we conclude that the definitive characteristics of this strategy are the integration of all channels and touchpoints, and the seamless customer experience with the brand, rather than with the individual channels (Huré et al. 2017). Even the first definition in the academic literature—that of Rigby (2011)—states in a clear manner that omni-channel retailing implies the full integration of multiple channels in all dimensions and activities, an opinion which was later assimilated by other academics. Regarding the integrative experience of consumers, the researchers Brynjolfsson et al. (2013) and Huré et al. (2017) posit that an omni-channel shopping experience is seamless (i.e. without rupture or friction) if the consumer can move effortlessly from one touchpoint to another. In other words, during a single purchase, customers can switch to a different selling channel at any point of the buying process and can perform the acquisition in any combination of channels they want. This is one aspect that is clearly implied in all the definitions.

3 Omni-Channel Retailing Strategy

Having understood the meaning of the omni-channel concept, the questions that arise are: what does strategic integration mean for retailers, and how it can be put into practice? This is where we found most inconsistencies in the literature. The means of accomplishing this remain unclear for researchers and practitioners alike. Also, it is not clear to what extent the various activities should be integrated or separated (Kembro and Norrman 2017). Besides that, there is another dimension often overlooked by academics, which is whether or not integration means identical characteristics of offers across channels. In other words, can the customer experience still be considered seamless or consistent (Piotrowicz and Cuthbertson 2014; Cao 2014; Beck and Rygl 2015; Hübner et al. 2016b) if there are differences between channels? Can the boundaries between the channels and touchpoints become blurred (Verhoef et al. 2015) without identical offers, prices, delivery, payment methods and promotion? Is it possible to have identical characteristics for offers across channels? And, if everything is identical for each channel, would this not lead to cannibalisation between channels?

Existing research needs to be supplemented with further investigation of the actual means of implementing this strategy (Picot-Coupey et al. 2016). Agreement still needs to be reached as to what exactly the implementation of omni-channel retail strategy involves for companies, since most researchers have avoided or ignored it. The remaining paragraphs introduce the views expressed so far regarding the practical implications of channel integration. They refer to several variables (Hübner et al. 2016a; Mosquera et al. 2017), the most important being the following, which we have classified into four dimensions, following the marketing mix structure:

3.1 Retailer Offers (Assortment, Prices and Communication About the Offers)

  • Assortment. There are two major trends in this field—one considers offers to be identical across channels, the other similar. Both options have advantages and disadvantages, so further research needs to be done on how to best implement the integration of channels.

Identical offers. Herhausen et al. (2015) point out that most omni-channel retailers use asymmetrical integration (online channels offer all the products offered by the physical channels, plus other items). Their research is important, being the first to clearly state that channels offering different assortments are not integrated, and that full integration means the same assortments across channels. Abdulkader et al. (2018) consider that companies are motivated to have all products available in-store as well as online, otherwise ruptures would appear between the two inventories, which would lead to customer dissatisfaction.

In the business literature, DHL Trend Research (2015, 4) asserts that ‘the customer experience in every channel must be identical and switching from one channel to another must be seamless.’ Deloitte (2015) considers that in omni-channel strategy, marketing, delivery and payment are carried out through multiple channels which are integrated, which also suggests that the offers should be identical.

Similar offers. Emrich et al. (2015) find that full integration is better that no integration but is not always superior to asymmetrical integration. Chopra (2016) argues that, in omni-channel retailing, it is not necessary to create all capabilities in every channel, but rather to assign the products and tasks that each channel is able to handle efficiently. Hübner et al. (2016a) consider the assortment of omni-channel retailers to be more extensive online than offline. In a similar spirit, Huré et al. (2017) try to define consistency from the customer’s point of view, and what retailers should do to accomplish this. They consider perceived consistency to be the consumers’ perceived coherence of the retailing mix of touchpoints. The researchers reach the conclusion that duplicating the retailing mix on each touchpoint would be irrelevant, considering their constraints and specificities, and that it is more advisable to replicate it in a flexible way. Kembro and Norrman (2017) forecast that in future the assortment will be larger online than offline.

  • Inventory. Kembro and Norrman (2017) suggest that inventory management and control should be integrated (for instance, by being visible across channels and jointly managed), despite the physical network being decentralised.

  • Product information. Providing customers and other members of the omni-channel with access to information about the offers on all channels allows for ‘anytime, anywhere’ problem-solving solutions. It is also useful for increasing store traffic (Bell et al. 2014). Customers can, for example, research the product online from home, then visit the physical store to evaluate the non-digital components of the product and, if satisfied, purchase the product in-store (Brynjolfsson et al. 2013).

  • Price and sales promotions tools. Saghiri et al. (2017) understand by integration in this area that all prices are synchronised, and any changes are visible to all members of the omni-channel.

3.2 Fulfilment (Logistics)

Omni-channel consumers expect to be able to combine the different channels in whichever way they find suitable for their purchasing, any time they want. This includes everything from pick-ups and returns of online purchases in the physical stores to personalised help from knowledgeable sales staff, as well as convenient online checkout procedures (Zhang et al. 2010). The integration of logistics allows consumers to trace, track and change the products, stock-keeping points, delivery or return points and transportation modes across all channels at any point during the purchasing process (Saghiri et al. 2017).

  • Shipping, logistics, picking up/delivery and return. In this area, a critical aspect is that of integration and centralisation (Kembro and Norrman 2017). Research by Cao (2014) and Hübner et al. (2016a) suggests that retailers increasingly centralise inventories and operations in one distribution centre. There is, however, another trend of decentralisation, because certain retail stores act as fulfilment centres, pick-up points and return points (Ishfaq et al. 2016). Supporting these findings, Wollenburg et al. (2018) identify three main logistics network configurations that omni-channel grocery retailers can choose from: a traditional bricks-and-mortar logistics network, an independent online distribution centre that covers a portion of online orders, or a single channel-integrated distribution centre.

  • Customer service. Integrated customer service implies the same or compatible service standards which are delivered by all members of the omni-channel (Saghiri et al. 2017). Omni-channel retailing forces both retailers and their suppliers to rethink their competitive strategies. In a market report published by DHL (2015), three strategic areas for the successful implementation of omni-channel retailing can be identified: personalised in-store shopping experience, personalised customer engagement beyond the store, and customer loyalty. The shopping experience can be enhanced by personalised service, making product information easily accessible, providing store shopping assistance from home (such as mobile phone applications that allow customers to create shopping lists at home), and on-the-go promotions targeting shoppers who are detected near a certain store. Omni-channel customer engagement continues via online channels, using applications that provide virtual expert advice, or via social media. Customer loyalty can be leveraged with the aid of automated ordering systems that simplify the process of replenishment for consumers and allow shoppers to customise products to their liking.

  • Payment (transaction). Transaction integration involves the possibility of using multiple payment instruments and securing accessibility to customer transaction data via various channels on behalf of the retailer, the consumer and other parties in the omni-channel (Saghiri et al. 2017).

3.3 Communication

Integration in this dimension is based on the requirement of omni-channels to focus on brand experience. It involves integrating all selling, promotion, communications channels and contact points. Omni-shoppers regard all selling channels as one entity.

  • Promotion. Promotional tools should be shared across all channels, channels should promote each other, and the message transmitted should be consistent (Saghiri et al. 2017).

  • Consumer data. Integration in this dimension implies the creation of a unified system where consumer information coming from online, offline, social and mobile data is gathered. This information includes not only personal characteristics, but also past transactions, visits to online or offline stores (to understand customer visiting patterns and the movement behaviours of customers and employees within each store), searches on websites, on search engines, likes on social media, and check-ins at various places. Footage from store security cameras and intercepted mobile phone and Wi-Fi signals are useful sources of information regarding visits to physical stores. The main challenges here relate to finding the appropriate means to collect data, store it, analyse it and then use it to enrich customer experience.

3.4 Internal Organisation

Omni-channel strategy involves the complete transformation of the retailer’s business model. It changes everything, whether it be management, organisation, human resources management, information systems, supply chain management, the design of processes, ordering systems or customer relationship management. The key concept of this makeover is integration. Picot-Coupey et al. (2016) suggest that the implementation process of omni-channel strategy can be carried out in two phases. The first stage deals with organisational, cultural, managerial, marketing and resources adjustments and integration. In the second stage, the retailing mix, information systems and customer relationship management need to be dealt with. Adjustments in organisational structure, organisational processes and organisational culture have not been tackled in the literature at all so far.

4 Conclusions

The main contributions of the current literature review to omni-channel retailing can be divided into four areas. First, it provides the most extensive overview of the term to date, both in academic and business literature (literature reviews and empirical research). Second, it differentiates the omni-channel business model from similar concepts of multi- and cross-channel retailing, which sometimes overlap in the literature. Another major contribution is that it identifies three major streams of views on the definition of the concept: the retailer view, the consumer view and both. Fourth, it highlights inconsistencies and gaps in the understanding of the practical implications of the concept, something that has not so far been tackled at all. These voids in the literature indicate important directions for future research. One area that remains underinvestigated is how exactly channel integration and a seamless experience for customers can be achieved; another being to what extent channels should be similar or complementary. Also, the attractiveness of omni-channels for geographic and demographic consumer segments would be a useful area of study.