The strength of an adhesive bond depends on the strength of both adherend and adhesive, the condition of the substrate surface, the thickness of the bondline, the weight of the components joined, and surface contamination. The strength of a material is measured either by crushing samples of it (compression testing) or by pulling them apart (tensile testing). The commercial tensile test machine (J. J. Lloyd Instruments Ltd. 15003 bench-top model has been used for strength testing of adhesives in the British Museum Research Section; the tests which can be performed with it include shear strength, tensile strength, peel strength, compressive strength, elastic modulus. The selection and preparation of test samples are also described.