Crime as a social phenomenon has customarily been examined as sets of occurrences which happen outside the boundaries of the legitimate social structure. Research by Lawrence E. Cohen and Marcus Felson suggests that more fruitful explanatory models of crime may be developed from the routine activity approach, an approach which regards crime as a routine activity in the same sense that everyday work may be regarded as routine activity. Such an approach is consonant with the precepts of human ecology. Human ecology as a theoretical model posits an interrelationship among the divergent parts of the social fabric. In such a scenario crime is regarded as another manifestation of a symbiotic social interrelation, one among many that flourish in the social whole. Crime, in this approach, is a routine activity, just as work is a routine activity.