Since the end of 2005, the ISO 20000 international standard for IT service management has been in existence, offering a normative management and organization concept for aligning the performance of IT services, and enabling companies to certify their compliance according this standard by third parties. There is a great interest in the standard, and the forecasts for the adoption and dissemination of the standard are, to a large extent, very positive. In contrast, some critical voices cast doubts upon the wisdom of normative management and organization concepts, and upon the possibility to verify or measure the conformity with public standards. Therefore it is our aim to study the current dissemination of the standard ISO 20000, and to examine the behaviour of companies adopting it. Till now there are no significant findings for questions like: Why do companies seek to conform to ISO 20000 and what benefits do they experience. Our results show that certified companies are motivated internally (process and quality improvements) and externally (marketing advantages) and do experience significant benefits. There are some significant differences between small and large companies certified as well as between internally and externally motivated companies.