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This book constitutes the proceedings of the 20th Collaboration Researchers´ International Working Group Conference on Collaboration and Technology, held in Santiago, Chile, in September 2014.
The 16 revised papers presented together with 18 progress papers and 3 invited talks were carefully reviewed and selected from 49 submissions. The papers published in proceedings of this year´s and past CRIWG conferences reflect the trends in collaborative computing research and its evolution. There was a growing interest in social networks analysis, crowdsourcing and computer support for large communities in general. A special research topic which has been traditionally present in the CRIWG proceedings has been collaborative learning.

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Understanding How Network Performance Affects User Experience of Remote Guidance.- Requirements for Ad-hoc Geo-referenced BPM with Microblogging.- Construction and Evaluation of a Collaboration Observation Model.- Monitoring Student Activities with a Querying System over Electronic Worksheets.- Two Make a Network: Using Graphs to Assess the Quality of Collaboration of Dyads.- A Programming Interface and Platform Support for Developing Recommendation Algorithms on Large-Scale Social Networks.- An Ambient Casual Game to Promote Socialization and Active Ageing.- Monitoring Collaboration in Software Processes Using Social Networks.- Supporting Teleconsulting with Text Mining: Continuing Professional Development in the TelehealthRS Project.- Defining a Design Space for Persuasive Cooperative Interactions in Mobile Exertion Applications.- Cooperative Work for Spatial Decision Making: An Emergencies Management Case.- Architecture of Mobile Crowdsourcing Systems.- A Semantic Approach to Shared Resource Discovery.- Performance Effects of Positive and Negative Affective States in a Collaborative Information Seeking Task.- Promoting Elderly-Children Interaction in Digital Games: A Preliminary Set of Design Guidelines.- Enriching (Learning) Community Platforms with Learning Analytics Components.- An Ontology Engineering Approach to Gamify Collaborative Learning Scenarios.- Group Formation Algorithms in Collaborative Learning Contexts: A Systematic Mapping of the Literature.- Evaluating Coordination Support Mechanisms in an Industrial Engineering Scenario.- Virtual Operating Room for Collaborative Training of Surgical Nurses.- JEMF: A Framework for the Development of Mobile Systems for Emergency Management.- The Semantic Web as a Platform for Collective Intelligence.- Engineering Peer-to-Peer Learning Processes for Generating High Quality Learning Materials.- Start-Smart as a Support for Starting Interaction in Distributed Software Development.- Social Media Collaboration in the Classroom: A Study of Group Collaboration.- An Effort of Communication Measure for Synchronous Collaborative Search Systems.- Using Structural Holes Metrics from Communication Networks to Predict Change Dependencies.- LOST-Map: A Victim-Sourced Rescue Map of Disaster Areas.- Mapping on Surfaces: Supporting Collaborative Work Using Interactive Tabletop.- How a Conflict Changes the Way How People Behave on Fandoms: An Investigation of Shippers Fight in Facebook Groups.- Choosing an Appropriate Task to Start with in Open Source Software Communities: A Hard Task.- Collaborating in the Fog: A Rich Description of Agile Software Development.- Motivating Wiki-Based Collaborative Learning by Increasing Awareness of Task Conflict: A Design Science Approach.

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