Using long-term personal background and registered criminal career data on 2,714 police-identified members of Dutch Outlaw Motorcycle Gangs (OMCGs), the current study examines Dutch OMCG membership and its association with members’ criminal careers. Results show that Dutch OMCG members differ from the average Dutch adult male population (N = 6,845,110) in terms of demographic, socio-economic, and criminal career characteristics. Furthermore, the findings corroborate statements that selection into Dutch OMCG membership has changed in recent years. Finally, the study explored the consequences of joining and desisting an OMCG on crime. The findings cautiously demonstrate that desistance from OMCG membership is associated with a drop in total and violent registered criminal behavior. No effects of joining an OMCG on crime were found, which is attributed to recent changes in OMCGs’ membership profile. Implications for future research are discussed.