The Internet of Things (IoT) envisions an ecosystem in which physical entities, systems and information resources bridge the gap between the physical and the virtual world. The existing heterogeneity in such physical entities, systems and information resources, intensified by the fact that they originate from different sectors and according to different perspectives, poses numerous challenges to the IoT vision. One of them is the need for interoperability, since capturing the maximum value from the IoT involves multiple IoT systems working together and, therefore, seamlessly interchanging information. However, successfully achieving interoperability requires coping with different aspects, not only technological but also social and/or regulatory ones. This talk will address how these aspects influence semantic interoperability, taking into account that such interoperability requires being aware of both the information interchanged and the data model (i.e., ontology) of such information.