Studies of climate change impacts on human health in the Pacific Northwest are limited. Research to date finds that climate change is likely to increase rates of heat related illnesses (including heat exhaustion and stroke); respiratory illness (e.g., allergies, asthma); vector-, water-, and food-borne diseases; and mental health stress. These impacts can lead to increased absences from schools and work, emergency room visits, hospitalizations, and deaths. Efforts to adapt Washington’s public health systems are in the early stages due in part to the limited information available to agencies.