Optimal treatment of tumors with orbital invasion may exceed the competences of an individual medical specialty and require interdisciplinary cooperation. The aim of this article is to present an interdisciplinary treatment concept based on the examples of intraorbital hemangioma and squamous cell carcinoma of the paranasal sinuses infiltrating the orbit. In addition to adetailed medical history and acomplete ophthalmological examination, adetailed imaging technique with standardized echography and tomography methods such as orbital thin-slice CT and/or in many cases MRI is essential for the primary classification of an intraorbital pathology. Depending on the type of pathology, apurely surgical procedure involving various disciplines such as ophthalmology, otorhinolaryngology, maxillofacial surgery, neurosurgery, and pathology, or an interdisciplinary treatment regimen including (neo)adjuvant radiotherapy or chemotherapy is necessary. Orbital tumors have awide range of potential pathologies, requiring complex surgical procedures and multimodal therapies. In case of infiltration of the paranasal sinuses or intracranial structures, an interdisciplinary team including neuroradiologists, oral-maxillofacial surgeons, otorhinolaryngologists, neurosurgeons, radiation therapists, ophthalmologists, pathologists, oncologists, and psycho-oncologists is essential for successful treatment.