The objectives of this project are: a) to build an analytical model to predict the damping capacity of a lap joint system consisting of composite adherends and a viscoelastic adhesive, and b) to carry out a systematic experimental study to verify the analytical predictions and to establish a data base on the damping capacity of various adhesively bonded structural joints. The proposed analytical model is an extension of a previous model formulated by the investigator to include adherends made of composite materials. The model will aid a designer to predict the system damping capacity of any single lap bonded joint system. The experimental activity involves testing several lap joint systems to compare experimental results with theoretical predictions. Next, the above experiments will be repeated on other types of bonded systems such as double-lap and butt jointed systems. The experimental data base for different configurations will also enable the designer to choose the right configuration from the damping point of view.//