A developmental process in which dormancy (sometimes called a dormant state) is induced, maintained or broken. Dormancy is a suspension of most physiological activity and growth that can be reactivated.

In plants and animals, dormancy may be a response to environmental conditions such as seasonality or extreme heat, drought, or cold. In plants, dormancy may involve the formation of dormant buds, and may be preceded by the senescence of plant parts such as leaves in woody plants or most of the shoot system in herbaceous perennials. The exit from dormancy in vascular plants is marked by resumed growth of buds and/or growth of vascular cambium.