Vascular malformations are congenital developmental defects of vasculogenesis, angiogenesis and lymphangiogenesis. A retrospective study of patients treated during the period of 1991 – 2010 was performed. All children with vascular malformations, who have been treated at the Department of Pediatric and Adolescent Surgery of the Medical University Graz were included into this study. During the acquisition of the data these parameters were analyzed: the discharge diagnosis, the clinical presentation, the results of conducted imaging, the histological findings, as well as the outcome after operative or non-operative therapy. The data have been analyzed by descriptive statistics and compared with the current literature. For successful treatment of patients with vascular malformations it is crucially important to be able to use all different treatment modalities alone or in combination, with a main goal to completely cure the patients and avoid the recurrence of these lesions.