This dissertation deals with the importance of fathers for the psychological and social development of infants in the western culture. After a short review of the historical development of father-child-relationships, this dissertation focuses on the competence of fathers of the present. The dissertation illustrates which influence fathers have on the socialisation of their children, on their development of gender identity and on their cognitive development. It also illustrates the consequences for children with fatherly deprivation. Finally, possibilities are described, how, after a separation, fathers can still play an important role in the lives of their children. Furthermore offers of social work support will be introduced.