This paper presents the main findings of quantitative and qualitative research into the criminal careers of about 1000 offenders who were involved in 80 extensively analysed cases of organized crime. The paper analyses how and when offenders become known to the criminal justice authorities, studies in depth the criminal careers of `starters' and analyses in detail the criminal careers of (ring)leaders and `nodal' offenders. Because social ties play an important role in organized crime, the paper emphasizes that the social opportunity structure, defined as social ties providing access to profitable criminal opportunities, is extremely important for explaining involvement in organized crime. It explains why certain offenders `progress' to certain types of organized crime whereas others become involved only later on in life. Social opportunity structure may also explain interesting phenomena such as `late starters' — people without any appreciable criminal history — and people in conventional jobs who switch careers.

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Criminological research over the last couple of decades has improved our understanding of cybercrimes. However, this body of research is regarded as still theoretically thin and not fully developed; more knowledge on the actors involved, their characteristics, and modus operandi is needed. Some publications recently suggested that organised crime is or might be involved in cybercrimes, which would have important policing implications, but evidence-based research on this point is still scarce and inconclusive. This article seeks to further this path of inquiry by providing a systematic analysis of 40 cases from The Netherlands, Germany, UK, and USA where criminal networks were involved in financial cybercrimes affecting the banking sector. It also assesses whether and to what extent these criminal networks meet the definitions of organised crime and discusses the theoretical and policing implications of our findings.

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