The availability of informal care will remain a key factor influencing future demand for formal services and the analysis cannot be dissociated from formal care. Based on the ‘unpaid care work–paid work–paid care work circle’, proposed by the International Labour Office, this paper focuses on the individual, interpersonal and organisational determinants that most influence quality care. This paper is based on 40 semi-structured interviews with care workers, in 16 Portuguese care homes, in one council in the metropolitan area of Lisbon. In spite of social change processes in the care worker profession in Portuguese nursing homes, in the last decade, in terms of numbers, age and education, the interviews allowed me to unveil qualitatively what the numbers hid: precarious working conditions, insufficient staffing, excessive workloads and long working hours, high rotation and insufficient skills. All these determinants have consequences not only on the quality of the care that these care workers can offer, but also on their physical and mental health, job satisfaction and work environment. The high demand of care needs due to the ageing of the population, calls for continued efforts in improving working conditions, and a national strategy to promote recruitment of a diverse, younger and more-qualified workforce. The professionalisation of care work must be integrated with migration and employment policies (improvement of job quality and working conditions).