This paper reports on explanatory qualitative research into the illegal economy within the hotel and catering industry in Belgium. Low profitability, exacerbated by pricing pressures customers and suppliers, predispose hotel and catering entrepreneurs to attempting a variety of non-legal modes of economic survival, including involvement in a ‘black market’ (‘off the books’ trading) between providers, suppliers and some customers. There are similar arrangements for the highly fluid workforce, whose hours and wages are only partially declared to the authorities, the untaxed payments then partially compensating for the low wages prevalent in the sector. Certain aspects of rules and regulations ‘backfire’, for example high VAT rates stimulate the grey economy; these and other evasions are being facilitated by sympathetic accountants skilled in hiding illegal transactions, and by complicit customers and suppliers. Illegal service providers and suppliers emerge to create an underground economy, and disputes are solved without recourse to the authorities. These sector conditions create an attractive, fertile soil for more serious criminal activities like human trafficking and money laundering activities.