Abstract : Since the end of the Cold War, military involvement in operations and training exercises has increased, while resources have declined. This situation can stress Service members, increasing personnel tempo, or PERSTEMPO, usually defined as "the number of days that Service members are away from their home station to perform their duties." This report clarifies definitions and measures of PERSTEMPO, summarizes research linking PERSTEMPO to retention, readiness, and quality of life, and presents the results of three analyses of existing Army data to identify effects of PERSTEMPO. Definitions of personnel tempo vary across Services, and are determined from self-reports and administrative records. Effects of PERSTEMPO have been inconsistent, and depend on individual and deployment characteristics. Results of data analyses indicate a modest relationship between PERSTEMPO and retention. At low levels, PERSTEMPO tends to increase retention; this positive relationship decreases at higher levels and may become negative. The analyses show inconsistent relationship between PERSTEMPO and self-assessed readiness. High levels of PERSTEMPO were associated with measures of family strain; relationships with financial factors and general satisfaction were negative, but quite weak. The analyses identified other variables regarding managing deployments that had substantial relationships with several measures of retention readiness and quality of life.