_Strategic Selling_ provides valuable insight into how to set up "Win/Win" situations: it begins by identifying the different kinds of "Buyers" in every sales situation, the roles they play, and what constitutes "Value" to them.
It then provides a mechanism for identifying what you do not "know" about the various Buyers, with the objective of finding out. It is an approach which helps you paint a complete picture of the dynamics at work in a selling situation, so that you can operate effectively within it.
Finally, it provides a mechanism for "keeping the sales funnel full" -- a challenge which most people operating in cyclical industries can identify with.
Following this methodology can help you ensure that you do not blunder around in ignorance in a Complex Sales environment -- you will know at least as much as the next guy, and probably much more. And you will be actively doing something about it.
Rackham's _SPIN Selling_ is a good complementary book to _Strategic Selling_, as it provides a tactical approach -- the "How To" as opposed to the "Why".
_Strategic Selling_ is an interesting -- though not uncomplementary -- contrast to Holden's _Power Base Selling_. Both approaches can provide insight into the inner workings of the Complex Sale; however, _Strategic Selling_ focuses less on manipulating the political forces at work, and may thus be more palatable for some