An impulse approach to linear viscoelastic behavior is developed that enables one to separate elastic from viscous response. The method relates the total stress impulse to the final state of deformation for viscoelastic fluids and to the total strain impulse for viscoelastic solids. Interestingly for solids, the relationships only involve elastic contributions and for fluids only viscosity terms enter the relationships. It appears that this method will be very useful in material characterization and can be used to follow the development of equilibrium elastic properties in thermosetting systems.