This paper offers a conceptually informed analysis of fostering and adoption social work and argues for more consistent inclusion of trans and non-binary people. The conceptual framework through which we explore current policy and practice is set out to provide clarity about the ways in which we employ the concepts of trans, gender diversity, and cisgenderism (a prejudicial ideology). We employ the notion of cisgenderism as a critical lens through which to overview fostering and adoption social work within the context of trans inclusion. Focus is turned to the existing literature relevant to trans parenting, trans-headed families, and the field of fostering and adopting. We highlight significant knowledge gaps in this regard. We then argue that if fostering and adoption social work is to embody inclusive practice with trans people, a new culture must be embedded to promote collaborative working, enhance knowledge, and improve service provision. The paper concludes by asserting that such an approach must be underpinned by an understanding, acceptance, and appreciation of people who identify as trans and/or as non-binary.