The results are based on the examination of the investigative records of a random sample of 581 docketed closed investigations of security violations; the investigations were conducted between 1948 and 1972. Characteristics of the way in which an offense is detected and characteristics of the offense itself were examined. Data analysis revealed a strong relationship between detection method (e.g., SEC surveillance efforts or referrals by insiders in illegal activities) and offense characteristics. There were substantial differences by detection method in the substantive nature of offenses, their temporal characteristics, their apparency, and the means by which they were executed. Different detection methods also produced differences in offender constellations and characteristics and their prior relationship to SEC; in the extent and patterns of victimization, the economic magnitude of the offense, and overall offense significance; and in the accuracy of the intelligence generated. Findings indicated that the choice of detection strategies involves important tradeoffs in the nature and quality of offenses uncovered. Each detection strategy provides a unique perspective on illegality. Policy implications and recommendations suggested by the results include: (1) changes in corporate governance, (2) requirements of corporate 'deviance audits,' (3) expanding theories of culpability, (4) redesigning and manipulating disclosure incentives, and (5) making better use of ongoing investigative intelligence. Appendixes include the data coding scheme and a listing of missing data, the coding forms, and complete numerical results in chart and graph form. A bibliography listing about 450 references is also provided.