Background: Collaboration between medical professionals from separate organisations is necessary to deliver good patient care. This care is influenced by professionals' perceptions about their collaboration. Until now, no instrument to measure such perceptions was available in the Netherlands. A questionnaire developed and validated in Spain was translated to assess perceptions about clinicians' collaboration in primary and secondary care in the Dutch setting. Aim: Validation in the Dutch setting of a Spanish questionnaire that aimed to assess perceptions of clinicians about interorganisational collaboration. Design & setting: After translation, cultural adaptation, and pre-testing, the questionnaire was sent to GPs and secondary care clinicians (SCCs) in three regions in the Netherlands. The responses of 445 responders were used to assess the validity and reliability of the questionnaire. Method: A confirmatory factor analysis (CFA) and an exploratory factor analysis (EFA) were performed to study the construct validity of the hypothesised factor model underlying the questionnaire. Test-retest reliability was evaluated using weighted Kappa statistics. Results: Results of the CFA indicated poor fit of the hypothesised factor structure. EFA, executed separately for each region, showed a highly unstable factor structure. The test-retest reliability analysis demonstrated low re-test reliability. Conclusion: The underlying factor structure of a Spanish questionnaire could not be reproduced. The construct validity and reliability of this questionnaire were insufficient to warrant use in the Dutch setting. This study demonstrates the need for evaluating validity and reliability of questionnaires in local settings.