The Joint ISPRS WG IV/7 and WG V/4 workshop Indoor-outdoor seamless modelling, mapping and navigation took place in Tokyo 21-22 May 2015. The workshop was opened with two keynotes, one of N. Yabuki (Towards the Intelligent environment by Sensing, Modelling and semantics) and another by S. Zlatanova on 3D indoor modelling and navigation. The 24 oral presentations, 18 posters and the technical exhibition have convincingly shown the importance of integrated indoor/outdoor 3D modelling and navigation. The workshop concluded that indoor applications are the most challenging issue to 3D geoinformation. The proceedings of the workshop are available here, and the closing presentation is available here.