This paper aims to explore the challenge posed by Bitcoin to regulators, particularly anti-money laundering regulators. Bitcoin is a crypto-currency based on open-source software and protocols that operates in peer-to-peer networks as a private irreversible payment mechanism. The protocol allows cross-border payments, for large and small items, with little or no transactional costs. Case studies and case law are examined as are relevant reports by regulators. Bitcoin is based on complex computer code supported by a robust community in a peer-to-peer network. Unlike other virtual currencies, Bitcoin appears to have obtained purchase and as such poses unique challenges to regulators. Bitcoin is at a nascent stage and the evolution of the virtual currency is difficult to predict. Those who study financial systems, anti-money laundering regimes and asset forfeiture laws will have an interest in this topic. This is a new and emerging currency; there is limited literature on the implications of this currency to anti-money laundering systems.