Activities related to refurbishment of the building stock as a percentage of all building work have been constantly growing in most central European countries over the last 20 years. The main argument in this paper is the need to improve knowledge about composition of the existing building stock, the dynamics of its transformation and to relate this to the different actors in property professions. A review is presented of traditional and new sectoral research approaches to partial or national building stocks to provide a context for assessing an integrated approach to the German building stock with methodological propositions for improving the synergy between different sectoral approaches. Detailed consideration is given to life cycle analysis, building product modelling, historical building research and new simulation techniques. Sustainability indicators and the integration of building stock, infrastructure and land use are discussed.