The illegal trade in wildlife and wildlife products globally is estimated to be worth more than USD72 billion annually, ranking alongside the illegal trafficking of narcotics, arms, and humans. This illegal trade, like other transnational crimes, involves a complex network of various individuals with the ultimate goal of moving the commodities from source to consumer. Based on the need to understand better the modus operandi of these criminal networks, this study interviewed 73 offenders incarcerated in 25 of South Africa’s correctional centres for offences related to the illegal trade in wildlife. The focus of the study was to uncover how offenders were recruited, the structure and modus operandi of these criminal networks, to gain insight into facilitators of these crimes on the economic value of the commodities at different stages in the supply chain and associated benefits for offenders. It was hoped that this research would also form the basis with which to engage with law enforcement to gain a better understanding of the current constraints and challenges faced by these agencies to perform their duties. Understanding the constraints and challenges of these agencies will enable interested stakeholders to identify solutions that may mitigate these constraints. This study found that most offenders either participated in the initial activity of the illicit wildlife supply chain - the poaching of the wildlife; or participated in supporting roles such as the transport or the storage of the wildlife commodity. Very few individuals (<10) were involved in the recruitment of offenders, or the sale of the commodity to domestic or international buyers or intermediaries. The wildlife commodities targeted by offenders included abalone, cycads and rhino horn. The structure of these networks typically involved the sourcing of the commodity, the subsequent trading between one or more intermediaries, before it was exported or sold to end consumers. Different facilitators were identified by the offenders including corrupt government and private sector individuals.