How can an organization decide in which BDS markets to intervene? This article draws on market assessments from all over the world to help managers decide when and how to launch such programmes. SEs are found to use BDS much less in some countries and for some services, but generalizations are unreliable, and it is usually necessary to draw up a profile of a market before it can be determined if a strategy that is effective in one country is appropriate for another. The article goes on to examine under what conditions of supply and demand for a service intervention will be most effective, and gives examples of appropriate interventions. Common assumptions, such as that business women use BDS less than men, or that price is a deciding factor in the choice of BDS, are examined.