Long-term monitoring campaigns were carried out in 35 German and 7 European office and administrative buildings, recording the operative room and ambient air temperature in fine time resolution. Further, short-term monitoring campaigns over two hot weeks in summer were conducted in non or partially retrofitted office buildings in Germany, built from 1960 to 1975. The buildings studied can be divided into six categories according to the cooling concept employed: without cooling, passive, air-based and water-based cooling, mixed-mode cooling and full air conditioning. Thermal comfort in summer is evaluated in detail using a standardized methodology in accordance with the comfort standard DIN EN 15251:2007-08. Thermal comfort is quantified by measurements of operative room temperatures and local meteorological conditions. In addition, useful cooling energy and electricity consumption were recorded. It is clearly demonstrated that it is feasible and valuable to compare different cooling strategies based on a consistent methodology. Furthermore, this methodology can be applied in day-to-day practice in the planning, commissioning and operation of buildings since these parameters are well-established and easily accessible