Crime patterns over time were examined using two measures of criminal activity; the number of reported offenses (either aggregated by month or year) and crime rates per 100,000 population. For the most part, total Index crime in Quincy increased substantially between 1972 and 1981, with property crime increasing more than twice as much as violent crime. The comparison of Quincy's crime with the Illinois cities of Carbondale, Danville, DeKalb, Freeport, and Galesburg indicated that some cities experienced increases in the number of violent or property offenses while others encountered the opposite trend. Taken as a whole, however, the number of reported Index crimes in the cities increased between 1972 and 1981. While the violent crime rate increased in Quincy, it decreased in the State as a whole; and the increase in Quincy's property crime was almost twice that of the State. By forecasting the number of aggravated assaults, burglaries, larceny-thefts, and motor vehicle thefts in Quincy for 1982 and comparing the actual 1982 figures with the predicted values, the degree of forecast accuracy for each crime was determined. Overall, the time series model used to forecast larceny-thefts had the highest predictive accuracy. Appendixes contain the population tables, crime definitions, and crime forecasts. Tabular and graphic data are provided along with a nine-item bibliography.