Over the last few decades, leniency programs recorded a successful history of identifying and dismantling cartels. But can authorities continue to almost exclusively depend on leniency programs going forward? In this short paper we explore the role of leniency programs in the next generation of cartel detection, and ultimately deterrence. Will it continue to be the dominant source of cartel detection, or will advances in data collection and analysis – so-called “big data” and “machine learning” – reduce the cost and increase the effectiveness of screening and artificial intelligence techniques? Will traditional leniency and whistleblower programs even remain effective in a future which may keep no “paper trail” of communications proving the necessary intent? Have cartels been changing and what does that imply for leniency? Have we learned the lessons from extensive rigging in financial markets? Do we need to revisit the entire detection approach?