This chapter is primarily concerned with the measurement of mechanical, thermal and chemical resistance characteristics and properties of adhesives for use in marine environments, providing an overview of test methods for design data generation and quality control purposes. It covers the testing of bulk adhesives and bonded joints (including sandwich structures) and includes a summary of commonly used tensile, compressive, shear, peel, cleavage and fracture toughness test methods. It provides guidance on issues relating to material properties obtained, specimen preparation and testing, and suitability for assessing environmental durability performance. The chapter covers natural weathering and accelerated testing, and methods for monitoring and assessing environmental degradation of bonded structures. Thermal and chemical analysis techniques are also included.