Within the European initiative OSACA (Open System Architecture for Controlswith Automation Systems) a company-spanning open control architecture has beendeveloped as of 1992. Since then the development of open control systems hascontinued until today. In 2008 a study was carried out with the objective toverify the results of 15 years of work for open control systems in Europe. Itought to identify especially the state of the art in the polled companies aswell as their wishes and goals for the future. This article contains the mostimportant results.