Overshoot of shear stress, sigma, and the first normal stress difference, N-1, in shear flow were investigated for polystyrene solutions. The magnitudes of shear corresponding to these stresses, gamma(sigma m) and gamma(Nm), for entangled as well as nonentangled solutions were universal functions of (theta)over dot tau(eq), respectively, and gamma(Nm) was approximately equal to 2 gamma(sigma m) at any rate of shear, (gamma)over dot. Here tau(eq) = tau(R) for nonentangled systems and tau(eq) = 2 tau(R) for entangled systems, where tau(R) is the longest Rouse relaxation time evaluated from the dynamic viscoelasticity at high frequencies. Only concentrated solutions exhibited stress overshoot at low reduced rates of shear, (gamma)over dot tau(eq) < 1. The behavior at very low rates, (gamma)over dot tau(eq) < 0.2, was consistent with the Doi-Edwards tube model theory for entangled polymers. At high rates, (gamma)over dot tau(eq) > 1, gamma(sigma m) and gamma(Nm) were approximately proportional to jr,,. At very high rates of shear, the peak of sigma is located at t = tau(R), possibly indicating that the polymer chain shrinks with a characteristic time tau(R) in dilute solutions.