The recent emphasis in criminological theory and research on “chronic offenders” assumes that involvement in crime is concentrated among a small group of offenders rather than being widespread in the population. To address this question, this study employs a longitudinal data base on criminal histories to estimate the prevalence of arrest—defined as the proportion of a population ever arrested—and the incidence of arrest—defined as the number of arrests incurred by those ever arrested—for an age cohort of young adults between the ages of 18 and 29. The results show that being arrested is a relatively common experience for young adults: nearly one-quarter of the entire cohort and one-third of the males in the cohort were arrested at least once. One of six males and two of five black males were arrested for an index offense. The data on incidence reveal the presence of a subset of “chronic offenders” who are responsible for a disproportionate number of arrests. However, defined in terms of three or more arrests for any offense, their numbers are smaller, but the data suggest it may be difficult to distinguish “chronic offenders” from “one-time” offenders because 60% do not recidivate. These findings suggest that the current preoccupation with chronic offenders may obscure the broader social structural factors that cause very large segments of the population to come into conflict with the law.