Several aspects of canopy flow are investigated. The problem of steady flow in a horizontally infinite canopy under neutral thermal stratification is treated theoretically. The resulting analytical model is then used as a boundary condition for a nonlinear numerical model designed to study transition regions near the leading and trailing edges of a canopy. This model shows a wave effect downstream from a leading edge observed in the field and laboratory. A tendency for a splitting of the flow near a windward canopy edge is also brought out.