Now there's a question… The answer is that both methods are equally valid. I always prefer to give employees a chance to input into the planning process. They know (or should know) the corporate goals so, if you engage them in the planning cycle, you can actually encourage them to work harder for something they planned for too.

Nevertheless, a good plan is a hybrid of both top down and bottom up planning. The key is to gather input widely - different levels of seniority & different departments - remember no-one has the monopoly on good ideas! Using both of these methods make the best plan you can and then, in Nike's words: "just do it"!