According to data from the 1999 National Survey of America's Families, programs that "stop the clock" when recipients work at least 30 hours per week could benefit many families. Approximately 613,000 families who receive TANF could automatically qualify because the primary caregivers in the families already work 30 or more hours per week. Another 192,000 TANF participants would qualify if they increase their hours of work from between 20 and 29 hours to 30 hours per week. An additional 750,000 eligible, non-recipients working at least 30 hours per week could benefit if they reenter welfare. The brief provides data for each of these three groups on employment, welfare participation, and the potential effects of this policy on their behavior and economic well-being.