As I'm getting ready to roll off the current engagement, I've been having conversations with the next vic-, er, person in line to "Assume the Position"® who was lamenting the lack of Rules of Engagement. Statement of purpose. Or even general direction.
When the conversation reached the point of ambiguity that the role doesn't even have a proper mission statement, I shared my personal guiding philosophy about being given executive direction:
David Reed says: MissionStatement = MissionStatement == null ? WriteOwnMissionStatement() : UseMissionStatementGiven();
It also helps to take that output back past the client for further validation, but of course, I have a higher chaos tolerance than many... Odd how it doesn't seem as funny now as it did with less sleep. Guess you had to be there.