Work Package 3 (WP3) aims at closing the semantic gap between humans and machines. The semantic gap will be tackled in terms of data (and its interpretation) as well as actions. WP3 is based on the recognition that people and machines produce and manipulate their data according to contextual implicit or explicit semantics. Machines have to “compose” and adapt to people – if the latter cannot provide a high level interpretation of the data – by learning from people and helping them achieve their local and global goals. The eventual target outcome is a set of methods for achieving symbiosis between people and machines, i.e., seamless interoperability. This can be reached through either a global consensus in terms of semantics and action or by means of an emerging “good enough social semantics” and a loosely coordinated collective action. From an operational standpoint, WP3 will also include aspects related to interfaces and persuasive technologies (captology).