Guidelines produced by some major international organisations create a misleading impression that Integrated Water Resources Management (IWRM) can be implemented in a standardized fashion. However, contextual conditions vary from place to place, and differences in beliefs, attitudes, customs, and norms sensibly influence interpretation and implementation. Experiences with IWRM in Oregon (USA) and Ontario (Canada) are examined with regard to scope, scale, responsibility, engagement, finances and financing, and review processes and mechanisms. Development of IWRM and the evolution of governance have been shaped by different concerns and beliefs. Oregon has adopted a locally-driven and entrepreneurial approach, whereas Ontario developed a co-operative inter-governmental approach. In both cases, IWRM governance has also evolved due to changes in funding and priorities, which have benefitted some catchments and communities more than others. Both cases provide positive examples of reflexivity and resilience, and demonstrate the importance of review processes and strong cross-scale connections for effective governance. While underlying principles may be relevant for other locations, it would be a mistake to think that either of the two approaches for IWRM could be replicated elsewhere in their exact form. Implementation of IWRM in other parts of those countries and the world should, therefore, start with careful analysis of the local context, and existing governance arrangements and governmentalities.