Samples cut from single crystals of olivine which had been deformed in the laboratory were annealed for 1 hour at either 0.1-MPa or 500-MPa gas pressure to study the effect of pressure on the kinetics of dislocation recovery in olivine. After an anneal the dislocation structure was examined by transmission electron microscopy and compared with the dislocation structure in an unannealed 'reference' sample from the same deformed single crystal. For the range of annealing temperatures used, 1525--1675 K, the density of free dislocations decreased by dislocation-dislocation annihilation. The activation volume and activation energy for this doslocation recovery process were obtained from an analysis of the decrease in dislocation density as a function of temperature, for the two hydrostatic pressures, in terms of second-order kinetics. This analysis yields V=11¿1 cm3/mol and Q=300¿15 kJ/mol.