Extensive job sample tests and multiple choice job knowledge tests were administered to approximately 370 men in each of four Army jobs: Armor Crewman, Repairman, Supply Specialist and Cook. Representative tasks in each job were analyzed and skill requirements were identified. This analysis and the correlations between job sample scores and job knowledge scores supported the proposition that knowledge tests are valid for measuring proficiency in jobs where skill components are minimal and where knowledge tests are carefully constructed to measure only information which is directly relevant for performing that job. (Author)