CollaborateCom is an annual international forum for dissemination of original ideas and research results in collaborative computing networks, systems, and applications. A major goal and feature of CollaborateCom is to bring researchers from networking, systems, CSCW, collaborative learning, and collaborative education areas - gether. CollaborateCom 2008 held in Orlando, Florida, was the fourth conference of the series and it reflects the accelerated growth of collaborative computing, both as research and application areas. Concretely, recent advances in many computing fields have contributed to the growing interconnection of our world, including multi-core architectures, 3G/4G wi- less networks, Web 2. 0 technologies, computing clouds, and software as a service, just to mention a few. The potential for collaboration among various components has - ceeded the current capabilities of traditional approaches to system integration and interoperability. As the world heads towards unlimited connectivity and global c- puting, collaboration becomes one of the fundamental challenges for areas as diverse as eCommerce, eGovernment, eScience, and the storage, management, and access of information through all the space and time dimensions. We view collaborative c- puting as the glue that brings the components together and also the lubricant that makes them work together. The conference and its community of researchers dem- strate the concrete progress we are making towards this vision. The conference would not have been successful without help from so many people.

Invited Short Papers.- A Distributed Collaborative Filtering Recommendation Model for P2P Networks.- Access Control for Cooperation Systems Based on Group Situation.- Web Canary: A Virtualized Web Browser to Support Large-Scale Silent Collaboration in Detecting Malicious Web Sites.- CalSWIM: A Wiki-Based Data Sharing Platform.- Examining a Bayesian Approach to Personalizing Context Awareness in Ubiquitous Computing Environments.- Invited Full Papers.- Smart Homes for All: Collaborating Services in a for-All Architecture for Domotics.- Archer: A Community Distributed Computing Infrastructure for Computer Architecture Research and Education.- Collaborative Search and User Privacy:How Can They Be Reconciled?.- Defending against Attribute-Correlation Attacks in Privacy-Aware Information Brokering.- Incentive and Trust Issues in Assured Information Sharing.- Combining Social Networks and Semantic Web Technologies for Personalizing Web Access.- Evaluating Security Policies in Pervasive Mobile Environments Using Context Information.- Towards Continuous Workflow Enactment Systems.- The RiverFish Approach to Business Process Modeling: Linking Business Steps to Control-Flow Patterns.- A Federated Digital Identity Management Approach for Business Processes.- SelectAudit: A Secure and Efficient Audit Framework for Networked Virtual Environments.- Collaborative Attack vs. Collaborative Defense.- Learning Models of the Negotiation Partner in Spatio-temporal Collaboration.- Full Papers.- Protecting Sensitive Information in Directory Services Using Virtual Directories.- TeleEye: An Awareness Widget for Providing the Focus of Attention in Collaborative Editing Systems.- Informa: An Extensible Framework for Group Response Systems.- Secure and Conditional Resource Coordination forSuccessful Collaborations.- RiBAC: Role Interaction Based Access Control Model for Community Computing.- A Constraint and Attribute Based Security Framework for Dynamic Role Assignment in Collaborative Environments.- Access Control Model for Sharing Composite Electronic Health Records.- Employing Sink Mobility to Extend the Lifetime of Wireless Sensor Networks.- Avoiding Greediness in Cooperative Peer-to-Peer Networks.- The Data Interoperability Problem as an Exemplary Case Study in the Development of Software Collaboration Environments.- Towards a Framework for Evolvable Network Design.- A Comprehensive Comparison of Trust Management Systems for Federation.- A Model of Bilinear-Pairings Based Designated-Verifier Proxy Signatue Scheme.- A Unified Theory of Trust and Collaboration.- Enabling Interoperable and Selective Data Sharing among Social Networking Sites.- Evaluating the Trustworthiness of Contributors in a Collaborative Environment.- Supporting Agile Development of Authorization Rules for SME Applications.- The Application of Human and Social Behavioral-Inspired Security Models for Self-aware Collaborative Cognitive Radio Networks.- GroupBanter: Supporting Serendipitous Group Conversations with IM.- The Effect of Personality on Collaborative Task Performance and Interaction.- Replication in Overlay Networks: A Multi-objective Optimization Approach.- An Undo Framework for P2P Collaborative Editing.- A Contract Language for Service-Oriented Dynamic Collaborations.- Monitoring Contract Enforcement within Virtual Organizations.- Using Epidemic Hoarding to Minimize Load Delays in P2P Distributed Virtual Environments.- A Battery-Aware Algorithm for Supporting Collaborative Applications.- Collaborative Graphic Rendering for Improving Visual Experience.- Analytics and Management of Collaborative Intranets.- Mashup Model and Verification Using Mashup Processing Network.- Automatic Categorization of Tags in Collaborative Environments.- A New Method for Creating Efficient Security Policies in Virtual Private Network.- Data Quality and Failures Characterization of Sensing Data in Environmental Applications.- Security through Collaboration in MANETs.- A Hybrid Key Predistribution Scheme for Sensor Networks Employing Spatial Retreats to Cope with Jamming Attacks.- Location-Based Mapping Services to Support Collaboration in Spatially Distributed Workgroups.- Serial vs. Concurrent Scheduling of Transmission and Processing Tasks in Collaborative Systems.- Ontology Support for Managing Top-Down Changes in Composite Services.- Trusted Translation Services.- Enabling Meetings for "Anywhere and Anytime".- Collaboratively Sharing Scientific Data.- IT Incident Management as a Collaborative Process: A Visualization Tool Inspired to Social Networks.