"Complex systems science provides an inter-disciplinary framework for understanding and responding to global change phenomena. It seeks to understand the behaviour of whole systems and provides a common language and a suite of analytical tools that improve communication and integration across disciplines. Because it addresses whole-system behaviours that are beyond the scope of reductionist science, it can help to reconcile the culture clash between scientific and non-scientific approaches to understanding our world. In February 2009, the Bulkley Valley Centre for Natural Resources Research & Management (BV Research Centre) and the Natural Resources and Environmental Studies Institute (NRESI) of the University of Northern British Columbia co-hosted a half-day informal public workshop on Complexity Science and Global Change in Smithers, BC. The purpose of the workshop was to stimulate dialogue about complex systems science and how it can be applied to the challenges of maintaining sustainable ecosystems and communities in the face of global change. Presentations and lively discussion sessions focused on the relationships among complexity, diversity and resilience, genetic complexity in tree and salmon populations, restoring functional diversity in tropical forests, self-organisation in legal systems and managing natural resources under uncertainty. This document summarizes the presentations and discussions."