Although the contribution of user participation to information sys-tems/information technology (IS/IT) project success is generally acknowledged in the literature, empirical evidence of the different attributes of user participation practices and the role of management in this process is still largely absent. This paper addresses two research questions: first, what determines the attitudes of users to ‘go with a new workflow’ in the case of a Business Process Management (BPM) system implementation? Second, how are these attitudes related to their user satisfaction and use of a BPM system? Based on theories of user participa-tion, management support and implementation effectiveness, a conceptual model is developed that defines a relationship between user participation, user attitudes and success metrics. To test the model, different research methods were used. First, survey data was collected among 78 end-users. Second, nine in-depth open interviews were held with the project manager, key-users and devel-opers. All respondents were employed by a large Dutch administrative social in-surance organisation that had customised and implemented a new and integra-tive BPM system.