Pervasive Collaboration is a crosscutting concern in many of today’s pervasive infrastructures and systems. It happens in many different forms and technical layers of device--‐ and network--‐mediated interaction, such as machine-to--machine (M2M) communication, interaction among smart home devices, wearable computing, inter--‐vehicle collaboration, as well as at the human layer in the form of participatory sensing, crowdsourcing, or content sharing through social networks. Addressing the challenges of these manifold ways of collaboration requires interdisciplinary research considering pervasive computing, context awareness, embedded systems, Internet of Things, and social networks. leading to a research area called Pervasive Social Computing. Researchers broaden the view on pervasive collaboration to include also remote actuation/control, mobile sensor data management as well as new forms of interaction, e.g. with public displays, wearable’s or among smart things. While not all pervasive social applications will cover all of these aspects, all of them provide means to interact and collaborate with contacts either in real--time or asynchronously while at the same time providing some link to the physical world (such as location of participants, devices or geo--tags or other relevant sensor information). Typical collaboration features include real--time chat, mutual presence information and activity streams, crowd sourcing of information, sharing sensor information, map--based tracking and interaction, proximity alerts, or even augmented reality games. Thus collaboration and social networking functionality on mobile devices is more and more tied together and creates a new social interaction experience for the participants. The aim of the PerCol workshop is to bring together researchers from the areas of pervasive computing and social computing to explore the possibilities and challenges of future Pervasive Social Computing applications. While the primary focus is on pervasive technologies for human--to--human interaction, we also welcome contributions about M2M interaction and coordination, opening a perspective of new technologies and applications for Pervasive Social Computing among humans and smart devices/things.