Due to recent advances in wireless technologies and the explosive deployment of mobile wireless devices, a pragmatic evolution of the generic Mobile Ad Hoc Networks (MANETs) paradigm (referred to as opportunistic networking) has emerged and is becoming increasingly popular as networking research area. Opportunistic networks (or OppNets for short) are a kind of challenged mobile ad hoc networks, where prolonged disconnections, unpredictable and unstable topologies, and partitions can frequently occurred. These types of networks are quite different from legacy ad hoc networks in the sense that disconnection and reconnection are common and link performance is extremely dynamic, making them very suitable to support pervasive networking scenarios. In OppNets, nodes are typically controlled by rational entities such as people. As such, by taking advantage of device mobility, information can be stored and forwarded over a wireless link when connection 'opportunities' arise (e.g. an appropriate network contact is met). Due to its nature and features, OppNet applications pose a number of research challenges in all areas of network, including system and protocol design, security, interoperability, deployment, applications and architectures, routing, performance, development and analysis, to name a few. The aim of this workshop is to provide a high profile, leading edge forum for researchers and engineers to present their latest research in the field of mobile opportunistic networking.