Over two decades ago, !he term characterisation covered just those techniques which measured the properties of polymers in solution in order to determine molecular weight and size. The discoveries of stereoregular polymers and polymer crystals created the need for new and advanced techniques for characterising chain structures and bulk properties. Further demands for new and improved characterisation methods for bulk polymers have resulted from the recent development and exploitation of multi phase polymeric systems, such as polymer blends, block and graft copolymers, and polymer composites. Today, therefore, characterisation is a very important part of polymer science. The polymer chemist must know the chain length, chain microstructure and chain conformation of the polymers he or she has prepared, i. e. the determination of molecular properties. The scientist involved in exploiting polymers in such applications as plastics, elastomers, fibres, surface coatings and adhesives must be informed on the morphology and physical and mechanical behaviour of his or her products, i. e. the determination of bulk and surface properties and their dependence on molecular properties. The techniques required for these determinations now cover an extremely wide field. Our aim has been to review a number of techniques critically and in sufficient depth so that the present state and future potential of each technique may be judged by the reader. Three criteria were used in the selection of techniques. First, we wished to present new methods which have been developed actively in the polymer field during the past five years.