Purpose– Benchmarking is increasingly considered a useful management instrument to improve performance in healthcare. The purpose of this paper is to assess if a nationwide long-term benchmarking collaborative between operating room (OR) departments of university medical centres in the Netherlands leads to benefits in OR management and to evaluate if the initiative meets the requirements of the 4P-model.Design/methodology/approach– The evaluation was based on the 4P-model (purposes, performance indicators, participating organisations, performance management system), developed in former studies. A mixed-methods design was applied, consisting of document study, observations, interviews as well as analysing OR performance data using SPSS statistics.Findings– Collaborative benchmarking has benefits different from mainly performance improvement and identification of performance gaps. It is interesting that, since 2004, the OR benchmarking initiative still endures after already existing for ten years. A key benefit was pointed out by all respondents as “the purpose of networking”, on top of the purposes recognised in the 4P-model. The networking events were found to make it easier for participants to contact and also visit one another. Apparently, such informal contacts were helpful in spreading knowledge, sharing policy documents and initiating improvement. This benchmark largely met all key conditions of the 4P-model.Research limitations/implications– The current study has the limitations accompanied with any qualitative research and particularly related to interviewing. Qualitative research findings must be viewed within the context of the conducted case study. The experiences in this university hospital context in the Netherlands might not be transferable to other (general) hospital settings or other countries. The number of conducted interviews is restricted; nevertheless, all other data sources are extensive.Originality/value– A collaborative approach in benchmarking can be effective because participants use its knowledge-sharing infrastructure which enables operational, tactical and strategic learning. Organisational learning is to the advantage of overall OR management. Benchmarking seems a useful instrument in enabling hospitals to learn from each other, to initiate performance improvements and catalyse knowledge-sharing.