We quote descriptions of expansion as business strategy.
The first order of business is understanding the difference between Sales and Expansion and why knowing the difference is so important. post 
A defining difference in the approach between account expansion and sales is how long your engagement with the customer has existed. post
One of the best reasons for expansion of business is to reach out to a new group of customers. Although you already have a well-mined customer base, there is always the opportunity to add new customers when you expand, especially if that expansion of business involves the introduction of new products and services. post
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Authors claim it is important to understand the distinction but seem to often get the roles reversed.