The vision for an Internet of Things calls for an open, inclusive and standards-based environment that fosters innovation. Reference to the Internet in this context relates to its transformational effect over closed proprietary systems, and its ability to enable a creative commons of innovation. Yet, the reality of the IoT today is one of fragmentation, characterised by information silos that are seeking to protect competitive advantage: Makers of innovative IoT products and services favour defensive strategies aiming to safeguard their investments; and, traditional automatic identification and data capture technology providers are accustomed to closed systems and wishing to perpetuate familiar business practices. Closed system strategies offer short term advantage as they locks out potential competitors. Yet, in the longer term they are inefficient for the market as a whole by placing barriers to the development of IoT ecosystems. There are two main reasons for this: Firstly, vertical integration increases complexity and thus decreases the quality of the end user experience of the IoT, which is determined ``by how products work together, in concert, with the rest of the ecosystem, not just by [...] any product on its own, no matter how good that individual experience will be'' as explained by Buxton. Second, vertical integration hinders the activation of network effects ---the value of a product or service increases with the number of people participating in it--- a critical factor for success perhaps best highlighted by the success of the Internet. The purpose of this workshop it to bring together researchers from academia and industry, practitioners, IoT vendors, and application-domain stakeholders to discuss the costs and benefits of emerging IoT ecosystems and the move from a vertical to horizontal model of integration. We seek submissions that cover all aspects of system-level architecture, service provision and network infrastructure as well as papers that consider domain specific concerns. We specifically encourage submissions that demonstrate or report on successful experiences in developing consensus across application domains in the development of IoT ecosystems.