The phase behavior and motional mobility in binary blends of polystyrene (PS) and poly(cyclohexyl methacrylate) (PCHMA) have been investigated by solid state C-13 NMR techniques. The blend miscibility has been studied by examining the H-1 spin-relaxation times in the laboratory frame (T-H(1)) and in the rotating frame (T-1 rho(H)) for the PCHMA/PS blends with various compositions and pure components. The T-1 rho(H) results show that PCHMA and PS are intimately mixed at the molecular level within the blends at all compositions. In addition, according to the results of carbon T-1 rho. relaxation time measurements, we conclude that mixing is intimate enough to cause a reduction in local chain mobility for PS, but an increase in side chain mobility for PCHMA.