Following legal and welfare restrictions imposed on asylum seekers in Sweden after 2015, new alliances emerged within and beyond professional social work and welfare institutions. This article examines how welfare professionals, in collaboration with civil society actors, have developed strategies to ensure that young asylum-seeking people have access to rights and welfare interventions that secure livelihoods. The data are based on interviews with welfare professionals and other actors involved in solidarity practices within civil society and asylum rights movements. The analysis draws on Joan Tronto's political ethics of care to conceptualise solidarity as a democratic, political and relational practice. It also engages with scholarship on transversal solidarity to describe how forms of care, resistance and collective responsibility emerge across institutional and civic boundaries in response to increasingly restrictive asylum law and practice. Drawing on Tronto's concept of 'caring with', we conceptualise ethical care as a practice shaped through cross-boundary organising and collective responsibility under restrictive migration policies. We analyse three strategies that welfare professionals have developed to counter the effects of increasingly restrictive asylum policy: open strategies from the inside, undercover strategies from the inside and becoming double agents of solidarity, through which care is enacted as a political stance.