Criminalisation Keeps Thailand’s Sex Industry in the Shadows Thailand’s sex industry remains illegal despite supporting a broad network of hotels, bars, restaurants, transport providers and tourism businesses. The article traces the trade from its earlier status as a regulated profession to its criminalisation during the 20th century. It argues that current laws conceal the industry’s economic contribution while leaving workers outside formal healthcare, social security and legal protections. During the Covid-19 pandemic, many businesses connected to nightlife received government assistance, while sex workers were largely excluded and faced severe financial and health difficulties. Bringing the industry into the formal economy could increase tax revenue, improve worker safety and make exploitation easier to report, although legal reform would also require confronting deep social stigma.