The Ninth International Conference on Model & Data Engineering (MEDI) will be held from 28 to 31 October 2019 in Toulouse, France. Its main objective is to provide a forum for the dissemination of research accomplishments and to promote the interaction and collaboration between the models and data research communities. MEDI’2019 provides an international platform for the presentation of research on models and data theory, development of advanced technologies related to models and data and their advanced applications. This international scientific event, initiated by researchers from Euro-Mediterranean countries, aims also at promoting the creation of north-south scientific networks, projects and faculty/student exchanges.