There are fewer and fewer 'steady jobs'. Instead our working life is looking more like a string of projects. I always advise people not to view their careers as an upwards path in the hierarchy of an organisation or society as a whole, but as a story of personal development, with each project as an opportunity to learn a lesson.
The good thing about working in projects is that it forces you to look in the mirror every now and then, and ask yourself the question whether you still love what you do. If not (enough) it's really time to move on. Make sure you never accept the answer 'I've gotten used to it'.
Two of the projects I'm working on at the moment are:
In Search of Excellent Government
Regional Innovation Systems