This chapter examines in detail the dynamics of braided rivers, including the initiation of braiding in a straight channel; the major mechanisms that promote braiding; the development of bar units in braided rivers; and the possible linkage of these units to those in meandering rivers. Other topics include the structure of flow in braided rivers and the relation of patterns of shear stress in braided rivers to patterns of erosion and deposition; to bar development, maintenance, and change over time; and to patterns of bank erosion. Mechanisms that lead to changes in channel locations through avulsions are reviewed and related to changes in hydrological conditions within braided rivers. The role of vegetation in braided river morphology is also explored. Numerical models of braided rivers that simulate changes in bed morphology and bank erosion are introduced.