Business process management technology is used at many sites as an instrument to improve the efficiency and agility of business operations. Currently, only a fragmented insight exists into the determinants for successful usage of this technology. The study in this paper is a first approach to more systematically investigate this issue, in particular by taking the end-user perspective into account. The study draws from quantitative data on two different implementations of business process management technology, as generated by the involvement of 342 end users. A major finding is that the proposed research model, inspired by the DeLone and McLean IS success model, has a very high power to explain the successfulness of the investigated implementations. It is found in particular that input and output quality and the quality of the IT support during operations are key factors that are more important than the characteristics of the actual system, which has important ramifications for IT praxis and research.