A comparison of NCS and Uniform Crime Report (UCR) data indicates that the likelihood of crime occurring is not uniformly distributed by time and place. NCS data show that robbery and assault occur disproportionately during the evening and night. Robbery occurs more often on the streets or other public places than in the home. Rates of violent personal and household crime are generally highest in the central city, and the majority of personal victimizations involve strangers as offenders. Population differences also are evident. Personal victimization is higher for males than females, the young than the elderly, nonwhites than whites, and nonmarried (single, divorced, separated) than married. Victim reports closely parallel official reports with respect to age, sex, and race variables. Differences between NCS and UCR counts occur for some offenses, particularly assault, and in some crime rate trends. NCS data suggest that crime rates remained relatively stable between the early 1970's and early 1980's, while UCR data indicate substantial increases during the 1970's and a decline about 1980. Finally, the individual's lifestyle or routine activities may be strongly related to risk of criminal victimization. 84 references. (Author abstract modified)