The effects of quenching and aging treatments on the structure, properties and precipitation kinetics in a Cu-22.3Zn-5.1Al (wt%) shape memory alloy have been investigated. The martensitic transformation temperature, M-S, during isothermal aging from 200 to 400degreesC decreases with aging time at each aging temperature. Aging at 400degreesC significantly reduces the tensile ductility and yield strength of this alloy. The periods of isothermal aging required to initiate precipitation of alpha-phase have been examined at various temperatures, and a time-temperature-transformation (TTT) diagram is drawn. The apparent activation energy estimated from the loss of shape memory recovery is similar to the activation energy of alpha-precipitation in the alloy.