The current thesis discusses how tools for analysing power are developed predominately for adults, and thus remain underdeveloped in terms of understanding injustices related to age, ethnicity/race and gender in childhoods. The overall ambition of this dissertation is to inscribe a discourse of intersecting social injustices as relevant for childhoods and child welfare, and by interlinking postcolonial, feminist, and critical childhood studies. The dissertation is set empirically within the policy and practice of Swedish child welfare, here exemplified by the assessment framework Barns Behov i Centrum (BBIC). It aims to explore how Swedish child welfare, as a field of knowledge, modes of knowing and knowing subjects, constitutes an arena for claims and responses to intersecting social justice issues. The material consists of BBIC primers and selected samples from, a total of 283 case reports from a Swedish social service agency. The case reports address assessments of children (0–12 years of age). This dissertation is based on four qualitative studies using discourse analysis, as well as analysis inspired by thematic and case-study methodology. Two studies focus on child welfare discourses in BBIC documents involving social problems and violence, and two studies are based on child welfare case reports. Studies I-II address child welfare policy and practice by analysing the conditions required for children to participate, in terms of children’s moral status and in terms of status of ‘evidencing’ needs for protection. Studies III-IV explore this further from the perspective of intersecting and embodied social injustices in childhoods. Together, the studies interconnect child welfare as a field of knowledge, modes of knowing and knowers with child welfare as a moral arena for claims to rights, recognition, and social justice. The synthesised findings point to child biowelfare, in which justice discourses are largely absent. Biowelfare is informed by a mode of knowing and ‘evidencing’ risks to children’s health and development, which are confined to scientific predicting-believing, seeing-believing by professionals and a moral economy of care, all of which constrain the idea that injustices are structural and intersecting. Biowelfare primarily responds to children as ‘speaking’ biological bodies, rather than as voices of justice. In this sense, injustices of an epistemological nature are interconnected with social injustices. When issues of justice are mobilised in case reports and policy, they come across as rather ‘unjust’, primarily confined to the sphere of the family home of racialised children and not connected to ‘general’ children. In addition to intersections of age, ethnicity/race and gender, class and health are fundamental to recognition and protection in biowelfare. Finally, the dissertation indicates the need for a moral economy which responds to intersecting social injustices such as racial, gender-based and ageist violence in childhoods, and violations of children’s bodily integrity. Key words: biowelfare, child protection, child welfare, critical childhood studies, critical social work, embodiment, epistemic injustice, epistemology, feminist theory, intersectionality, justice subjectivity, moral economy, moral subjectivity, participation, postcolonial theory, poststructural social work, social justice, violenc