This book constitutes the thoroughly refereed conference proceedings of the 13International Workshop on OWL: Experiences and Directions, OWLED 2016, and the 5th International Workshop on OWL: Reasoner Evaluation, ORE 2016, held in Bologna, Italy in November 20, 2016. The Workshops were co-located with the 20th International Conference on Knowledge Engineering and Knowledge Management, EKAW 2016. The 11 revised full papers, 3 short paper and one invited talk presented were carefully reviewed and selected from 27 initial submissions. The papers are trying to bridge the gap between ontology engineering practices and software engineering with the aim of  describing reuse methods employed throughout the ontology development cycle; modeling/terminological decisions, alignment and comparison between ontologies, how ontologies are stored, versioned, distributed and consumed over the Web. Chapter “Use Cases and Suitability Metrics for Unit Ontologies� is available open access under a Creative Commons Attribution 4.0 International License via link.springer.com.