Purpose - The purpose of this paper is to study the antecedents of service innovation success in the knowledge-intensive business services context, especially why the participation of frontline employees and multiple organizational units is not enough for succeeding in knowledge-intensive service productization. Design/methodology/approach - A multiple-case study of two polar cases with longitudinal data, participant observation, and key personnel interviews. Findings - Case evidence indicates that frontline employee participation and cross-unit collaboration are not sufficient antecedents for successful service productization. Instead, to facilitate employee knowledge sharing, managers need to align the project goals with the goals of participating employees, and promote trust among the project workgroup. Moreover, to enable effective cross-unit collaboration, managers need to facilitate the establishment of common vocabulary for productization work and services, and to resolve any emerging conflicts between participating organizational units. Practical implications - The findings indicate the importance of enabling knowledge sharing and cross-unit collaboration for service productization. The identified antecedents translate to practical strategies for achieving these. The results also highlight the importance of bottom-up service innovation, and the management of service innovation on the group level. Originality/value - The study indicates that common antecedents for successful service innovation may not be sufficient in the knowledge-intensive context, calling into question the assumptions about individual and group behavior in service innovation, and suggesting the importance of multi-level perspective on service innovation.