Heidi Taylor - through her excellent blog heidi-taylor.com - sheds some light on marketing plans and strategy.  And as always, she is spot on. 

A marketing plan is not a strategy, and the two are all too often confused.

She illustrates her argument using Kipling's Just So stories.  

The What, Why and When make up your strategy, the How, Where and Who make up your plan.

A simple and clever guide - and one to remember.