Oculo-auriculo-vertebral spectrum (OMIM164210) is a phenotypically and probably also a genetically heterogeneous disorder, characterized by anomalies of the ear (mostly microtia), hemifacial microsomia, and defects of the vertebral column. Associated clinical findings include anomalies of the eye and brain, and developmental delay. We have evaluated the clinical data and photographs of 53 unrelated patients with OAVS, all presenting with either isolated microtia or preauricular tags in association with hemifacial microsomia as minimal diagnostic criteria; five had a positive family history for OAVS. Based on the main clinical findings and unilateral or bilateral involvement, we have developed a new classification system for OAVS, consisting of six subgroups. There is a statistically significant correlation between the subgroup and number of associated clinical findings, and a statistically significant difference regarding prognosis in uni- and bilaterally affected patients, suggesting that this classification is clinically relevant to the categorization of patients with OAVS. The newly developed scoring system (two points for each main clinical finding and one for each associated clinical finding) presented here, also aids prognosis, especially for delay of motor development and brain anomalies, and statistical analysis revealed significant clustering between different clinical findings of OAVS confirming the clinical impression previously published by several authors.