Unilateral hypoplasia in the middle and lower face has different etiological causes. A standardized interdisciplinary treatment of children is demonstrated with the help of ten operated cases and nine children in observation. Depending on the missing structure of the anatomical regions the areas are reconstructed. A pre- and postoperative orthodontic treatment is part of the concept. With an operative intervention in childhood, it is possible to gain in most cases a more normal appearance till adulthood.