AbstractThis article reports on the effects of the Social Support Act (Wmo) in the Netherlands, implemented in 2007. The Dutch Act resembles the current European political interpretation of citizenship: stressing self-responsibility in one's personal life, fighting against elements of the welfare state that are believed to be invasive and implying a shared responsibility of government and civil society for the care of socially vulnerable groups. Data were collected on the basis of two surveys evaluating the effects of the Wmo for voluntary organisations and professional non-profit institutions in social care and welfare (2007: N = 383 and 2009–10: N = 389). In addition, in-depth interviews with stakeholders and qualitative case studies were carried out. The study yields several paradoxical policy outcomes. Contrary to the objectives of the Social Support Act, a ‘revitalisation’ of the Dutch civil society – in terms of a greater contribution to social goals and policies – remains problematic, whilst professional entities thrive under the new governmental élan. Other paradoxical outcomes stem from a too-dogmatic approach to the social participation of people with severe mental disabilities. Instigating the socialisation of these groups through mandatory measures can in practice increase their isolation. To reduce unintended effects, the Social Support Act should take into account the divergent capacities of vulnerable groups and prioritise the psychological safety of clients over political and administrative policy objectives.