Storage is a characteristic feature of most plants, particularly perennials, and the subject has been thoroughly reviewed according to its chemistry and physiology (9, 40, 59, 80, 133, 139). However, in ecology much of the information on storage is based on observation rather than experimentation, and experiments often fail to confirm common perceptions of the nature and dynamics of stored reserves. For example, clipping studies show that not all carbohydrates are available to the plant, even thought hey are considered to be stored reserves. In this review we suggest criteria for defining storage in ecological and economic contexts in order to examine the costs and benefits of storage. We then evaluate the evidence for, and ecological importance of, different types of storage. We discuss storage in relation to vegetative growth and reproduction, but we ignore storage in seeds and fruits in this review (41,85) because the purposes and constraints on storage differ somewhat between vegetative and reproductive tissues.