This volume contains the proceedings of the 15th International Conference on Conceptual Structures (ICCS 2007), which is an annual event that, for the ?rst time, was hosted in the UK. Conceptual structures focus on the representation and analysis of concepts, events, actions and objects with applications in – search, softwareengineering, manufacturing and business.The conference brings together researchersin computer science, information technology, arti?cial int- ligence, philosophy and a variety of applied disciplines to explore novel ways that information technologies can be leveraged to assist human reasoning and interaction for tangible business or social bene?ts. Conceptual structures can be used to augment human intelligence by facilitating knowledge integration, de- sion making, the creation of intelligent software systems and the exploration of implicit structures. The theme for this year’s conference was "Conceptual Structures: Kno- edge Architectures for Smart Applications." Knowledge architectures give rise to smart applications that allow enterprises to share meaning across their int- connected computing resources and to realize transactions that would otherwise remain as lost business opportunities. Conceptual structures and smart appli- tions integrate the creativity of individuals and organizations with the prod- tivity of computers for a meaningful digital future. A focus of ICCS 2007 was on papers that apply conceptual structures in business and technological settings. Other submitted papers covered researchin conceptual structures, which is s- ported by mathematical and computational theory, including formal concept analysis, algorithm design and graph theory, and a variety of software tools.