Introduction: 6,000 to 8,000 rare diseases are known worldwide. Around 15% of all the rare diseases known can manifest themselves in the dental, oral, and maxillofacial areas. About one-third occur with a cleft lip and/or palate. In the fields of medicine and dentistry, not much is known about the clinical manifestation, diagnostics, and treatment of rare diseases. Sources of information are not easily accessible or are not known. The aim of this working group is therefore to establish an open-access database for rare diseases with orofacial/craniofacial manifestations which is available as a source of information not only for oral surgeons and dentists, but also for patients and their families. Material and method: In 2011 work was begun on trawling through databases such as Orphanet, OMIM, and Pubmed for rare diseases and on assessing the contents. Since 2013 the information gained has been incorporated into the web-based, freely-accessible ROMSE database, including current specialist literature, with the diseases allocated to relevant categories. The database is freely accessible at http://romse.org. Results: So far, 478 rare diseases with orofacial/craniofacial manifestations have been entered into ROMSE. These include 145 diseases with cleft lip and/or palate. Two institutes now offer special consultation times for rare diseases with oral involvement, providing an initial place of contact for patients. Conclusions: Rare diseases and their symptoms make great demands on medicine, oral surgery, and dentistry in regard to diagnostics and treatment. A database for recording rare diseases with changes in the oral and maxillofacial areas can help in making diagnoses and considering options for treatment in dental and oral medicine. Special consultation times and centres of expertise should be offered on a nationwide scale. Keywords: rare diseases, database, orofacial manifestation