THEORETICAL ISSUES REGARDING URBANISM AND CRIME ARE BRIEFLY REVIEWED AND DATA ARE PRESENTED ON TRENDS IN VIOLENT CRIME BY SIZE OF COMMUNITY. THE STUDY LARGELY USES RATES OF VIOLENT CRIME AS THE PHENOMENA TO BE EXPLAINED. THESE RATES ARE MEASURED AS THE NUMBER OF PERSON OFFENSES RECORDED AND PUBLISHED BY THE FEDERAL BUREAU OF INVESTIGATION PER 100,000 RESIDENTS OF COMMUNITIES IN WHICH THE CRIME OCCURRED. A CLOSER EXAMINATION IS THEN MADE OF VIOLENT CRIME RATES FOR CALIFORNIA COUNTIES AND A SHORT EXAMINATION IS MADE OF COMPARABLE FOREIGN DATA. ANALYSIS OF THESE DATA LEND WEIGHT TO TWO RELATED ARGUMENTS: WITH RESPECT TO VIOLENT CRIME, SOCIAL AND BEHAVIORAL CONTRAST BETWEEN URBAN AND RURAL PEOPLES IS NOT DECLINING, THUS CHALLENGING THE COMMON CLAIM THAT MASSIFICATION TENDS TO ERASE COMMUNITY DIFFERENCES. MOREOVER, RECENT DATA ON VIOLENT CRIMES SUGGESTS THAT URBAN-RURAL DIFFERENCES MAY SYSTEMATICALLY EXPAND AND CONTRACT OVER LONG PERIODS, RATHER THAN FOLLOW ANY PUTATIVE SECULAR TREND (WIDENING AND NARROWING) ASSOCIATED WITH MODERNIZATION. THESE HISTORICAL VARIATIONS IN COMMUNITY DIFFERENCES CAN BEST BE UNDERSTOOD BY POSITING THAT VIOLENT CRIME IS A CULTURAL PHENOMENON AND THAT CULTURAL CHANGES EMERGE IN URBAN CENTERS AND DIFFUSE FROM THEM TO RURAL AREAS. A MODEL OF A CYCLICAL FLUCTUATIONS IS PROPOSED IN CRIME RATES IN WHICH URBAN CYCLES PRECEDE RURAL ONES. TABULAR DATA, NOTES, AND REFERENCES ARE INCLUDED. (MJW)