The study was prompted by estimates that 80 percent of the vests sold to police are not worn daily and that police agencies' efforts to increase use have not had a lasting effect. The agencies surveyed were Troop D of the Missouri State Highway Patrol, and the Greene County (Mo.) Sheriff's Department and Springfield, Mo., Police Department. Findings showed that the wear rate is higher than assumed and that officers prefer lighter, cooler, thinner, and more flexible vests without the loss of ballistic capabilities. Comfort is the main consideration. In addition, officer participation in the purchasing of armor is the most important factor in achieving a high wear rate. Further research on field officers' needs and priorities should be conducted before adopting proposed Federal legislation on the subject.