This paper describes the diagnostic techniques and experimental methods used for investigating the properties of implosion compression in direct drive . Several diagnostic techniques with fine time, space and spectrum resolution are employed to obtain the information concerning implosion, such as radiation un iformity on the capsule, compression symmetry, volume compression ratio, implosi on time, implosion velocity and average electron temperature of the capsule shell. Some of the typical results measured in the experiments are presented and as imple discussion is also given.