PurposeThis paper contributes to the theory of the relationship between human resource management (HRM) and innovation at small- to medium-sized enterprises (SMEs) by conducting a conceptual analysis of the question why Germany boasts by far the highest number of “Hidden Champion” SMEs. This is done by case studies from the army and public financial management of aid disbursal in developing countries. Implications for HRM at SMEs are discussed.Design/methodology/approachConceptual analysis using case studies.FindingsContributing towards filling the gap concerning theoretical underpinnings of the link between HRM and innovation, we suggest that interdisciplinary work from relevant organisational case studies indicates that the concept of institutional design to provide motivational incentives may be relevant, especially concerning high performance systems with bundles of HRM practices. Specifically, the fundamental principle of subsidiarity is found to be important.Research limitations/implicationsThe research is broadly applicable to organisations of all kinds, as the diverse case studies indicate. We point towards tentative implications for the firms that account for the majority of the work force, namely SMEs, and among them the most successful ones, the so-called “Hidden Champions”.Practical implicationsHR managers can improve motivation, performance and innovation by decentralising decision-making as far as possible, while ensuring the overall organisational goals are well understood and shared, and resources are dedicated to train and educate staff. Additionally, the conception of rank-order competitions complements the institutional design.Social implicationsGreater productivity and material performance as well as greater job satisfaction via larger autonomy and decision-making power on the local level can be achieved by the application of subsidiarity as key HRM configuration. This can be employed at SMEs, as discussed, but also other organisations. Further, the principle of subsidiarity and the greater emphasis on staff training and education may help reduce inequality.Originality/valueOur paper contributes towards filling the gap in the literature on the link between HRM and innovation, by identifying the role of subsidiarity. We introduce an interdisciplinary perspective, with contributions from economics and psychology, among others. We also contribute to the history of HRM.