Challenges for Semantically Driven Collaborative Spaces -- Shared and Personal Views on Collaborative Semantic Tables -- Wikis and Collaborative Systems for Large Formal Mathematics -- From Ontology to Semantic Wiki – Designing Annotation and Browse Interfaces for Given Ontologies -- A Semantic MediaWiki-based Approach for the Collaborative Development of Pedagogically Meaningful Learning Content Annotations -- Discovering Wikipedia Conventions Using DBpedia Properties -- Soft and Adaptive Aggregation of Heterogeneous Graphs with Heterogeneous Attributes -- Okkam Synapsis: Connecting Vocabularies across Systems and Users.

This book constitutes the thoroughly refereed post-workshop proceedings of the Second International Workshop on Semantic Web Collaborative Spaces, SWCS 2013, held in Montpellier, France, in May 2013, and the Third International Workshop on Semantic Web Collaborative Spaces, SWCS 2014, held in Trentino, Italy, in October 2014. The 6 revised extended papers presented were carefully reviewed and selected from 10 submissions. The papers are grouped in topical sections on challenges in collaborative spaces, modeling collaborative communities and the role of semantics, semantic MediaWiki communities, and exploiting semantics in collaborative spaces.