The Ontario Climate Change and Health Toolkit has been developed to meet the public health challenges of a changing climate in Ontario. This toolkit has been designed to support an adaptive and resilient public health system that anticipates, addresses and mitigates the emerging risks and impacts of climate change. This toolkit includes the: Ontario Climate Change and Health Vulnerability and Adaptation Assessment Guidelines: Technical Document; Ontario Climate Change and Health Vulnerability and Adaptation Assessment Guidelines: Workbook; and Ontario Climate Change and Health Modelling Study: Report.