No matter where you're located in your company's "food chain," your job is never guaranteed. Mergers, acquisitions, sell-offs or simple cost-cutting could eliminate your position. Or your own actions--insubordination, fraud, misrepresentation, a poor relationship with co-workers--could get you fired.
Sure, the unemployment rate hovers around three percent. Job security might not be your biggest concern. But it doesn't hurt to know how to keep it that way: