We reviewed publications, websites, and field observations to explore the health and welfare impacts and administrative effectiveness of different legal approaches to sex work. We identified three broad legal approaches: (1) prohibition, including the unique Swedish law criminalising sex workers' clients; (2) licensing; and (3) decriminalisation. Each of these models is employed under one or more jurisdictions in Australia. We make preliminary observations on their consequences and conclude that, on initial impression, decriminalisation may offer the best outcomes. However, more rigorous population-based research is needed to properly assess the health and welfare impacts of legal approaches to sex work.