We refer to an ongoing discussion around micro-institutionalist approaches in the neo-institutional perspective on organizations ([ 1 ], (2), (3), [ 4 ]). The paper addresses how organizations respond to pressures from competing and potentially conflicting institutional logics (1). An understanding of organizational responses is drawn from the conflict of the professional, rational -bureaucratic and market logic (5). By investigating the implementation of the process improvement standard CMMI (Capability Maturity Model Integration) in software development organizations, we show different organizational responses to these conflicting institutional logics. A CMMI certificate for a software development process embodies all three institutional logics: (a) the market logic due its potential of a competitive advantage resulting from an increased trust in the final software product by customers, (b) the rational-bureaucratic logic by exercising managerial control over compliance of software development processes with the CMMI standards requirements and (c) the professional logic in form of its inscribed expertise in software engineering. Our empirical results show three different responses: ( I) an integrative approach that balances between the conflicting logics, (2) a durable and a (3) non-durable response which favor market and rational bureaucratic logic. At the same time, the three investigated cases highlight different consequences for the software developers and their professional logic. The findings of the study contribute to neo-institutional theory by delivering empirical insights on how differently logics are managed in the day-to-day practice of actors. Thus, we call for further empirical investigation on the micro-institutionalist level. A link of the neo-institutionalist perspective to the theoretical perspective of the professions is suggested.