On 21st September 2021, Brendan Bromwich (Principal Engineer, Asset Management and Investment Planning, Mott MacDonald) hosted a CECAN webinar reviewing the application of Participatory Systems Mapping and Plural Rationality in practical system challenges in water and environment. The webinar draw on project experience including Water Resources South East’s Regional Resilience Plan and Defra’s Systems Analysis for Water Resources, and concluded by looking at emerging challenges in the water sector including nested operation of catchment, regional and national water resource management systems.