This paper discusses the experience of Transactie Monitoring Nederland (TMNL) — a collaboration between ABN AMRO, ING, Rabobank, Triodos Bank and De Volksbank, established in July 2020 to enhance financial security and compliance within the Dutch financial sector. The paper explores TMNL’s impact, the key lessons learned from its implementation and operation, best practices and its potential future role in safeguarding the integrity of the financial sector. As the paper explains, there is a growing consensus that more can be done to strengthen the framework for fighting financial crime through public–private partnerships and increased data/information sharing. To this end, TMNL works to identify potentially unusual transaction patterns that are not visible to individual banks in isolation, underscoring the significance of collaboration and information sharing among financial institutions (and with other key players in the prevention ecosystem), and developing a united front against financial crime. The paper calls for the integration of artificial intelligence and machine learning in identifying complex patterns and anomalies in transaction data and emphasises the need for this to happen in a secure, sustained and viable fashion. It also underscores the ongoing need for regulatory adaptability, arguing that as financial crimes evolve, regulatory frameworks must be dynamic to address emerging challenges effectively. In conclusion, the paper provides valuable insights into the successful implementation of collaborative compliance efforts and the continuous adaptations required to combat financial crime.