It's by Spencer Johnson, M.D. I'm just about finished with it and it's pretty darn good. It talks about change and how different people react to and deal with change. I know personally I tend to become very anxious and agitated when things start to change.
I read this years ago - I can't remember exactly about it, so I might have to read it again. I just remember that it was good! I read it because one day at the bank, a bank teller was reading it in between customers. The bank had handed it out to all their employees.