A call to represent the current diversity of family forms in attachment research.

As family forms become increasingly diverse, their underrepresentation in attachment research is glaring. Although attachment theory aims to explain the influence of early relationships, studies have disproportionately focused on mothers. Even when other attachment figures are considered, the research is typically limited to fathers in biparental mother-father families. In this piece, we report on the wide variety of family configurations worldwide, and how children experience care from multiple attachment figures. Drawing from the Child Attachment Studies Catalogue and Data Exchange (CASCADE), we assess the current state of attachment research with regard to diverse family configurations. Out of the available records in CASCADE, only four of 2,320 studies (0.2% of available studies) involved samples of diverse families. We conclude by issuing an explicit call for research that acknowledges and explores diverse family forms and propose strategies to improve reporting and research practices to promote more inclusivity of diverse family forms.