This study examined the psychological well-being of fathers and father–child relationships in families with a 7-year-old child conceived by donor insemination. Twenty-four donor insemination families and comparison groups of 25 egg donation and 32 unassisted-conception families were assessed using a standardized interview and questionnaires administered to the father, and father–child dyads participated in an observational assessment of father–child interaction. On the basis of perspectives from Parental Investment Theory and stress-related models, it was expected that donor insemination fathers would show raised levels of psychological problems and a poorer quality of parenting and have more conflictual relationships with their children than genetically related fathers in egg donation and unassisted-conception families. These hypotheses were not supported by the findings. Instead, it seems that commitment to parenthood may be more important than genetic relatedness for positive father–child relationships.