Captured thinking: You don't allow your financial people to keep their numbers in their heads. Financial reports are the lifeblood of the numbers side of any business, no matter what size. It should be no different with marketing. Your written document lays out your game plan. If people leave, if new people arrive, if memories falter, if events bring pressure to alter the givens, the information in the written marketing plan stays intact to remind you of what you'd agreed on.
Marketing plans include overall marketing strategies, pricing, sales tactics, services and warranty policies, advertising and promotion, distribution, product desires, market research or market research. The steps to conduct market research are: identifying problems, collecting data, analyzing and interpreting data, drawing conclusions and taking action.