This European Standard specifies the procedure for the determination of the in-plane shear strength and modulus of fibre composites. The procedure is based on the uni-axial tensile stress-strain response of a ± 45° laminate which is symmetrically laminated about the mid-plane. This standard is applicable to composite laminates manufactured from unidirectional tape or woven fabric reinforcement. This standard does not give any directions necessary to meet the health and safety requirements. It is the responsibility of the user of this standard to consult and establish appropriate health and safety precautions.