As time passes, I'm becoming more and more convinced that you can improve the performance of almost any organization by tightening the alignment of its people, plans and practices around a shared purpose.  While it's often hard to figure out where to start, when onboarding into an organization, it's almost always best to get clear on the shared purpose and then tackle the people.

This is because the people pose the greatest opportunities and threats.  Get the people on your side and they'll help you figure out the plans and practices.  If the people rally against you, they will undermine anything else you do.