In an 8-year period, from 1985 to 1992, 89 children presenting with a supracondylar humeral fracture were treated at the Department for Traumatology, Philipps-University, Marburg. All dislocated fractures (n = 48) were treated surgically. The majority (n = 34) of dislocated fractures were reduced open by a radial and an ulnar approach and subsequently stabilized using crosswise introduced K-wires. All fractures were differentiated retrospectively according to the degree of dislocation, the presence of associated injuries, the type of treatment chosen, and the function outcome. Fifty-two patients were reexamined. Clinically relevant varus deformities (4% of cases) and impaired elbow function were observed only in cases where anatomic fracture reduction or fracture fixation was not obtained. Critical analysis of our results and the literature led us to the development of a new, treatment-oriented classification of supracondylar humeral fractures in children. We consider fractures that are dislocated less than 20 degrees, and where dislocation exists only in a saggital plane to be type A fractures. These fractures can be treated conservatively. Type B fractures are fractures that are dislocated more than 20 degrees only in the saggital plane, but with remaining ventral or dorsal cortical bony contact between the fragments. In these fractures, we perform closed fracture reduction and K-wire stabilization. Type C fractures are fractures with rotational deformity, fractures dislocated in a frontal plane and fractures dislocated in a saggital plane with loss of cortical bony contact between proximal and distal fragments. Type C fractures should be reduced open by both a radial and an ulnar approach and subsequently stabilized using K-wires, introduced crosswise.