The Swedish contribution to the International Geodynamics Project (IGP) is concentrated in two major fields of research, the Caledonian Research Project and the Study of Postglacial Earth.Movements. Both projects are financed by the Swedish Natural Science Research Council This paper summarizes the research activities of the Caledonian Research Project (CRP). The IGP-CRP is an inter-disciplinary study involving geologists and geophysicists with a wide range of interests and drawn from institutions in Göteborg, Lund, Luleå, Stockholm and Uppsala. Various collaborative projects with foreign institutions are in progress. Research is concentrated geographically in a Geotraverse some 300 km long and 200 km wide, extending from the Caledonian Front in the vicinity of Östersund to the Norwegian coast west of Trondheim. CRP research is organized in nine subprojects, namely, Basement and Deep Structure, Basement—Cover Relationships, the Särv Nappe, the Seve—Köli Nappe Complex and Higher Tectonic Units, Pre-orogenic History, Palaeo-magnetism, Experimental and Theoretical Tectonics, Experimental and Theoretical Studies of the Mechanism of Rock Deformation, and Experimental and Theoretical Studies of Metamorphism within the Geotraverse Area. Priority is given to research leading to a better understanding of crustal movements during the Caledonian evolution, during both the accumulation of the late Pre-Cambrian to Devonian sequences and their orogenic deformation.