Managing and monitoring disturbances of forest ecosystems and natural hazards are increasingly critical endeavors as proliferating pests and diseases, changing frequency and intensity of wildfires, windstorms, and invasive species and increases in ungulate herbivory are causing novel responses. This chapter describes the characteristics of natural and anthropogenic disturbances and focus more specifically on disturbances of boreal and temperate forests, with particular emphasis on hurricanes as an example of multiple disturbance processes. Ecological resilience is one factor in the vulnerability of a forest to disturbances, determined in part by the strength of its ecosystem memory. Many disturbances will increase in frequency, intensity, or both due to climate heating. Monitoring forest conditions and detecting changes are necessary to develop early warning systems for predicting disturbances and especially natural disasters. Monitoring is the key to detecting change and managing to ensure the continued flow of benefits to society.