Cross-selling is the action or practice of selling among or between clients, markets, traders, etc. or the action or practice of selling an additional product or service to an existing customer. This article deals exclusively with the latter meaning. In practice, businesses define cross-selling in many different ways. Elements that might influence the definition might include the size of the business, the industry sector it operates within and the financial motivations of those required to define the term.
The objectives of cross-selling can be either to increase the income derived from the client or clients or to protect the relationship with the client or clients. The approach to the process of cross-selling can be varied.
Unlike the acquiring of new business, cross-selling involves an element of risk that existing relationships with the client could be disrupted. For that reason, it is important to ensure that the additional product or service being sold to the client or clients enhances the value the client or clients get from the organization.
In practice, large businesses usually combine cross-selling and up-selling techniques to enhance the value that the client or clients gets from the organization (and vice versa).
Cross-selling of professional services 
Benefits that can accrue to the customer include the efficiency and leverage that result from using a single supplier for multiple products. When buying complex professional services, like consulting needed to make and integrate an acquisition, the use of one firm reduces the fingerpointing that is common when a problem occurs in an area that straddles two or more services; if only one firm is responsible, fingerpointing is eliminated.
For the vendor, the benefits are also substantial. The most obvious example is an increase in revenue. There are also efficiency benefits in servicing one account rather than several. Most importantly, vendors that sell more services to a client are less likely to be displaced by a competitor. The more a client buys from a vendor, the higher the switching cost.
Though there are some ethical issues with most cross-selling, in some cases they can be huge. Arthur Andersen's dealings with Enron provide a highly visible example. It is commonly felt that the firm's objectivity, being an auditor, was compromised by selling internal audit services and massive amounts of consulting work to the account.
Though most companies want more cross-selling, there can be substantial barriers:
- A customer policy requiring the use of multiple vendors.
- Different purchasing points within an account, which reduce the ability to treat the customer like a single account.
- The fear of the incumbent business unit that its colleagues would botch their work at the client, resulting with the loss of the account for all units of the firm.
Broadly speaking, cross-selling takes three forms. First, while servicing an account, the product or service provider may hear of an additional need, unrelated to the first, that the client has and offer to meet it. Thus, for example, in conducting an audit, an accountant is likely to learn about a range of needs for tax services, for valuation services and others. To the degree that regulations allow, the accounts may be able to sell services that meet these needs. This kind of cross-selling helped major accounting firms to expand their businesses considerably. Because of the potential for abuse, this kind of selling by auditors has been greatly curtailed under the Sarbanes-Oxley Act.
Selling add-on services is another form of cross-selling. That happens when a supplier shows a customer that it can enhance the value of its service by buying another from a different part of the supplier's company. When one buys an appliance, the salesperson will offer to sell insurance beyond the terms of the warranty. Though common, that kind of cross-selling can leave a customer feeling poorly used. The customer might ask the appliance salesperson why he needs insurance on a brand new refrigerator, "Is it really likely to break in just nine months?"[original research?]
The third kind of cross-selling can be called selling a solution. In this case, the customer buying air conditioners is sold a package of both the air conditioners and installation services. The customer can be considered buying relief from the heat, unlike just air conditioners.
- A Life Insurance company suggesting its customer sign up for car or health insurance.
- A wholesale mobile retailer suggesting a customer choose a network or carrier after one purchases a mobile.
- A television brand suggesting its customers go for a home theater of its or another's brand.
- A laptop seller offering a customer a mouse, pen-drive, and or accessories.
See also 
- Bait and switch
- Choice architecture
- Contract of sale
- List of marketing topics
- Permission marketing
- Predictive analytics
- Selling technique
- Value added selling
||This article includes a list of references, related reading or external links, but its sources remain unclear because it lacks inline citations. (February 2008)|
Wittmann, Georg (2006). Cross-Selling Financial Services to Small and Medium Enterprises via E-Banking Portals. Göteborg: Proceedings of 14th European Conference on Information Systems. p. 8.