The best definition of stress that I have come across is "the physical or psychological response to a perceived demand on our lives". Often, this response is the result of trying to fulfill an expectation that was set prior to our arrival or by someone else. Key reminder: what was prior isn't necessarily a priority now. The trick is to manage the best ideas now rather than trying to complete someone else's concepts that were formed yesterday.

Rick Warren, author of The Purpose Driven Life, discusses this in a recent podcast called "How to Balance a Busy Life".