In the process of creating a care plan or finding a placement for children, assessment of their health and developmental needs will be undertaken. This can involve the interpretation of complex family history information and may also include undertaking and interpreting the results of genetic testing, when within professional guidelines. This study explores opinions, knowledge about and experiences of adoption professionals in relation to genetic information and testing in Wales. Semi-structured qualitative interviews were conducted with six social workers and seven medical advisers. The data were transcribed and thematically analysed. Themes included the challenges to collation of family history, how the willingness of professionals to undertake genetic testing in children awaiting adoption was altered by the availability (and non-availability) of family history information, and the uncertainty that genetic information can generate for professionals and prospective parents. Uncertainty for both professional groups emerged from apparent inconsistency in current practice and from concern over their own lack of genetic knowledge. As new genetic technologies increase the scope of uncertainty, there is a need for social workers and medical practitioners working in adoption to have a greater understanding of genetics alongside opportunities to discuss cases in a multidisciplinary setting when appropriate.