The rising number of private care arrangements in which live-in migrant care workers are engaged as a functional equivalent to family care calls for special attention by policy makers and formal long-term care providers on their implications for quality assurance and professional standards in the long-term care sector. Austria is one of the first countries in Europe where tangible legal measures have been taken to regulate this area under the heading of ‘24-hour care’, typically provided by middle-aged women. Reform measures went beyond policing and control mechanisms, including also incentives and tangible subsidies for all stakeholders. This paper contributes to a better understanding of their impact on the transition from informal to formal economy, focusing on quality assurance and working conditions. Based on empirical data and findings from semi-structured interviews with relevant stakeholders, a framework for the analysis of ‘illegal markets', based on Beckert and Wehinger's theory, is used to discuss potential implications in terms of valuation, competition and co-operation for policy in Austria, and to draw lessons for other countries. Results indicate that even after efforts to ‘legalise’ migrant care, the sector remains a ‘grey’ area within modern labour market legislation and quality management. This is due to the very nature of personal care, low professional status associated with care work and the reluctance of political stakeholders to regulate private household activities.