The Second EAI International Conference on Cognitive Internet of Things Technologies October 26th and 27th, 2015, Rome, Italy Recent studies and reports have evinced that the Internet of Things will have a huge impact on our society. Conservative estimates predict there will be 50 billion of connected devices by 2020. Besides connecting real-time such numbers of objects, managing them and the data they generate will also pose challenges whether each of these produce no more than few bytes per minute in a very remote location or heavy data-streams within the heart of "resource rich" smart cities. Simply looking at the sheer size of these numbers, it is clear that competing for end-user attention will be the main hurdle to overcome. To put it in Mark Weiser's words, these objects will have to "weave themselves into the fabric of our everyday life" leveraging on the features of a more Cognitive IoT where connected "things" become more intelligent and more autonomous. All this abundance of information sources generated by the ubiquitous computing phenomena opens new perspectives for many Artificial Intelligence branches, such as decision making strategies, reasoning, learning, etc. Cognitive IoT aims at gathering enthusiastic researchers and practitioners from AI and IoT-related areas sharing the common goal of addressing the new challenges posed by the Cognitive aspect of IoT, by using new or leveraging existing Artificial Intelligence techniques.