This Note describes a successful approach for tracking a highly mobile group of junior high school transferees and thereby minimizing attrition in a longitudinal study of adolescent behavior. Students were tracked through the home or the new school. When students were located through the latter route, the authors sent the surveys directly to the school itself instead of asking for a home mailing address. This approach avoided asking school officials to give out personal information and enhanced the likelihood of the survey being delivered. Overall, the tracking effort cut nonresponse attributable to between-school mobility by two-thirds and reduced the attrition rate by one-half. The new-school strategy, which was a particularly effective technique for finding student transferees, accounted for a significant proportion of that improvement.