This book constitutes the refereed proceedings of the 9th Metadata and Semantics Research Conference, MTSR 2015, held in Manchester, UK, in September 2015.The 35 full papers and 3 short papers presented together with 2 poster papers were carefully reviewed and selected from 76 submissions. The papers are organized in several sessions and tracks: general track on ontology evolution, engineering, and frameworks, semantic Web and metadata extraction, modelling, interoperability and exploratory search, data analysis, reuse and visualization; track on digital libraries, information retrieval,...