Abstract: This paper presents the stress and strain distrihution obtained numerically in thethickness direction in the central region of symmetric composite laminates underuniaxial exlension and in-plane pure shear loading. It is shown that in the symmetricangle-ply laminates,near the interlaminar surface,thereis an interlaminarboundary-layer effect.The abrupt change of the fiber orientation at the interlaminarsurface causes a high concentration of stresses and a local three dimensional stress state.