The off-axis and ±45° axial tests are not only effective but also low cost methods for the determination of in-plane shear modulus in individual unindirectional lamina, because they avoid the difficulties of producing a pure state of shear stress experimentally. Possible test approaches for more general composites, including multidirectional laminates, are developed from an investigation into the transformation equations for orthotropic mechanical properties, laminate theory, and the mechanical advantages of the ±45° test. Other possible test approaches for the indirect determination of shear modulus in laminates and pultrusions are developed from the formulas used to correct for shear deformation in flexural test. The proposed tests should be more economical to perform than tube torsion or rail shear tests. They should also provide relatively uniform shear stresses over larger portions of the specimens than the notched specimen type tests.