Never, never, never, assume.
My husband had worked for his very successful, worldwide company for 21 years. At his last evaluation, he received a raise and a bonus for making his yearly goals - nothing new, he always received great evaluations from a variety of supervisors throughout his career.
Three days after his last wonderful evaluation, he and half his department were given 90 days notice. Nothing personal, just business. They had decided to change the expansion plans they had been training my husband's department for.
Up-to-date skills, a large network of contacts, and a six month emergency fund provide the best security for me.
Sorry if I sound overly negative but I want to spare people from the disbelief my husband went through.