The foundation stone for the success story of Rosenheimer Sommer Informatik GmbH was laid with the foundation of the company in 1996. The objective of the company is the development and distribution of individual and standard software in the fields of building physics and statics. This also includes the performance of all service tasks such as consulting, training and support. Within a short time Sommer Informatik GmbH was able to achieve the position of market leader in the field of isothermal and frame U-value calculation. WINISO® has established itself as the industry solution for thermal calculation for windows and facades. Building physics software solutions from Sommer Informatik now stand worldwide for extremely precise calculations with a high degree of detail. The same goes for the GLASGLOBAL® software solution, which is now successfully used in almost all major window construction companies in Western Europe for the structural dimensioning of glass in accordance with DIN 18008. The intensive cooperation of Sommer Informatik GmbH with wellknown companies leading the industry, the Institute for Window Technology, numerous universities and scientists as well as a large number of engineers working in this field of expertise guarantees a constant future-oriented further development of the renowned building physics software programs.