Purpose - To examine Gerald Mars' contribution to scholarly understanding of workplace crime by revisiting his seminal work, Cheats at Work, and to explore developments in the forms, patterns, and implications of cheating at work since its publication. Methodology/approach - This chapter critically reviews Cheats at Work and explores the changing nature of fiddling over time using the analytical framework and four associated occupational categories of workplace crime identified by Mars. The review is based on three main sources: recent scholarly literature on misbehavior, deviance, and employee misconduct; cases from industrial law reports, newspapers, and social media; and the views of informants conveyed directly to the authors. Findings - The analytical framework that Mars contributed remains useful even if the boundaries of the occupational categories of workplace crime are now more blurred, with some jobs and fiddles spanning categories. Although, technology has changed the nature of fiddling, new forms have emerged as old ones have disappeared. Social implications - Three decades after publication of Mars's study, it is evident that fiddling remains a normal, albeit covert, activity in many jobs and occupations. His typology continues to be valuable for explaining patterns, forms, and implications of cheating at work. Originality/value of chapter - Given the growing interest in the forms and implications of misbehavior and workplace resistance, this chapter provides an opportunity for reflection on the enduring salience of Cheats at Work, thirty years after its publication.