Polarization modulation infrared linear dichroism has been used to study the molecular orientation and relaxation of polystyrene/poly(2,6-dimethyl 1,4-phenylene oxide) (PS/PPO) miscible blends, containing up to 20% PPO, during and after a rapid uniaxial deformation above T-g. In general, it is found that both the PS and PPO chain orientation functions increase with stretching rate and PPO content, and decrease with temperature. For all blends investigated, between T-g + 5 and T-g + 13 degrees C, the relaxation occurs at the same rate for PS and PPO and, therefore, the relaxation times calculated are similar indicating, under those conditions, a strong relaxation coupling between the two polymers at both short and long times.