As the falling real-estate and stock markets erode their savings, many aging Americans are delaying retirement, electing labor over leisure in uncertain times.

A three-decade veteran at International Business Machines Corp., Dick Boice had planned to sell his house, pack up and move to Arizona with his wife, Lauren, to take early retirement. But two months after the January date he set to exit the work world, Mr. Boice, who is 59 years old, is still on the job. He figures he'll stay put for another couple of years.

The...