Violations were committed by 1,923 or nearly one-fourth of the probationers studied. New crimes, primarily minor offenses, accounted for 48.8 percent of misbehaviors. The majority of violators did not engage in further violations. The study also found that substantial variation existed in officer responses to similar violations, that application of more severe sanctions was no more likely to affect the seriousness of chronic violators' subsequent misbehaviors than application of more lenient ones, that the decision to revoke did not result in the rapid removal of offenders from supervision, and that officers frequently left punishment of rearrested probationers to the courts. The relatively minor nature of most violations and the infrequency of chronic violating behavior suggest that the application of controlling strategies, such as electronic monitoring and intensive supervision, may be excessive and consequently unnecessarily costly. 2 notes, 3 figures, 3 tables, and 14 references (Author abstract modified)