According to many scholars, cooperation, together with solidarity and sense of the community, upheld the advent of the Homo Sapiens on the Planet. After more than 200 thousand years, we argue that the advent of the Homo Digitalis will be based on the same tenets, but supported by advanced cooperation tools in a deeply changed digitalised world. Cooperative Information Systems (CIS) facilitate the cooperation between individuals, organizations, smart devices, and systems of systems, which provide flexible, scalable and intelligent services to enterprises, public institutions and user communities. As a result, people can interact, share information and work together across physical barriers in cloud-based environments. The Cooperative Information Systems (CIS) paradigm integrates the research results from many related computing areas, such as: distributed systems, coordination technologies, process management, knowledge management, collective decision making, and systems integration technologies, while the core are the organizational and business models that help shaping at best the technological solutions. In recent years, several innovative technologies have emerged: Cloud Computing, Service Oriented Computing, Internet of Things, Linked Open Data, mash-ups, Semantic Systems, Collective Awareness Platforms, Processes as a Service, etc. New technologies have created the need for new forms of diffused social computing, an even tighter integration of data and knowledge with large-scale collaboration platforms, by crowdsourcing and community-centric cooperation. The notion of business processes and workflows has evolved from prescriptive approaches to agile, adaptive and goal-driven solutions. Emerging collaboration platforms are introducing flexibility, transparency, dynamic re-planning as key features, supported by new ways of monitoring and managing KPIs, analyzing environmental information, e.g., adopting complex event processing techniques. Building next generation CIS requires technical breakthroughs in terms of dynamic, reliable and secure collaborative information technologies to overcome the tough challenges that traditional approaches fail to face. Several challenges are put in front of us, from the revival of the socio-economic system to reforms of citizens’ engagement in the public institutions, from participatory Open Innovation in modern enterprises to social cohesion and democratic models in a renovated public administration. All such challenges require a deep rethinking of CIS that represent their fundamental technological support in addressing specific application domains, such as e-Business, e-Commerce, e-Government, e-Health, and e-Science. The CoopIS conference series have established themselves as major international forums for exchanging ideas and results on scientific research and practical experiences in the fields mentioned above. As in previous years, CoopIS'15 will be part of a joint event with other conferences, in the context of the OTM Federated Conferences ("OnTheMove"), covering different aspects of distributed information systems.