Scope Many organizations and individuals have relied on electronic collaboration between distributed teams of humans, computer applications, and/or autonomous robots to achieve higher productivity and produce joint products that would have been impossible to develop without the contributions of multiple collaborators. Technology has evolved from standalone tools, to open systems supporting collaboration in multi-organizational settings, and from general-purpose tools to specialized collaboration grids. Future collaboration solutions that fully realize the promises of electronic collaboration require advancements in networking, technology and systems, user interfaces and interaction paradigms, and interoperation with application-specific components and tools. The 21st EAI International Conference on Collaborative Computing: Networking, Applications and Worksharing (EAI CollaborateCom 2025) will be held in Shanghai, China, and will continue to serve as a premier international forum for discussion among academic and industrial researchers, practitioners, and students interested in collaborative networking, technology and systems, and applications. Topics General Topic Architectures, protocols, and enabling technologies for collaborative computing networks and systems Collaboration in social media Collaborative e-education, e-learning, and collaborative computing in large scale digital libraries Collaborative information seeking Collaborative mobile networks and infrastructures Collaborative technologies for fast creation and deployment of new mobile services Collaborative, context-aware infrastructure Computer supported collaborative work with distributed systems Energy management for collaborative networks Methodologies and tools for design and analysis of collaborative user applications Models and mechanisms for real-time collaboration Peer-to-peer and overlay networks, systems, and applications Simulation, performance evaluation, experiments, and case studies of collaborative networks and applications Software design, testing, and experimentation technology for collaborative networking and applications Theoretical foundations and algorithms for collaborative networks, applications, and worksharing Tools for collaborative decision-making processes Visualization techniques, interaction devices and visual languages for collaborative networks and applications Topic 1. Internet of Things (IoT) and collaboration Collaboration in pervasive and cloud computing environments Collaborative sensor networks, unmanned air and ground vehicle networks and applications Collaborative, location-aware mobile systems/applications Cyber-physical systems Collaboration in health-care environments Participatory sensing, crowdsourcing, and citizen science Topic 2. Collaborative Data and Workflow Management Big data and spatio-temporal data in collaborative environments/systems Collaboration in data-intensive scientific discovery Collaboration techniques in data-intensive computing and cloud computing Data management and middleware support for collaborative information systems Distributed collaborative workflows Workflow management for collaborative networks/systems Web services technologies and service-oriented architectures for collaborative networking and applications Topic 3. Collaboration with artificial intelligence Autonomic computing and quality of services in collaborative networks, systems, and applications Group-driven composition of systems from components Human-centric ubiquitous collaboration Human-robot collaboration AI-Powered Information Seeking and Sensemaking Collaborative Intelligence: Humans and AI Joining Forces AI-Driven Learning Analytics in Computer-Supported Collaborative Learning (CSCL) Edge-Cloud Generative AI in Mobile Networks Combining Multi-Agent Systems and Artificial Intelligence of Things (AIoT) Topic 4. Security and Trustworthy Trust and Explainability in AI AIoT Security and Privacy Collaborative Trust Evaluation in AIoT Networks Intelligent Secure Trustable Things (InSecTT) AI Trust, Risk, and Security Management (AI TRiSM) Security, privacy and trust management in collaborative networks, systems, and applications Trustworthy collaborative business processing in virtual organizations