The biggest challenge for retired police officer Jim Stephens is instilling a good work ethic in the young security guards who work for his security company in tiny Smock, Pa. So he pairs the newcomers with older employees—and some of them are as old as 75. In fact, 14 of the 24 people who work for Sonrise Security Patrol Inc. are older than 55, a demographic Stephens credits for his company’s success.