The current theory of viscoelasticity of polymer fluids deals with their response to time-dependent macroscopic perturbations on arbitrary time scales. We use scaling methods to calculate the elastic and dissipative moduli G' and G '' on length scales that range between monomer size and macroscopic dimensions for several important models of polymer solutions. We find that while both moduli decrease rapidly with decreasing length scale, G' is more strongly suppressed than G '' at large wave numbers. Possible experimental tests of our predictions are discussed.