One of the primary engineering concerns in tsunami (seismic sea wave) research is the final stage of wave run-up, run-down and overland flows - processes which can cause severe damage in a populated coastal community. These effects are usually complicated by the three-dimensional aspects of the problem, including impact with coastal structures and propagation over the nearshore bathymetry; to which these long waves are highly responsive. Most of the existing research on tsunami run-up is primarily two-dimensional: There is a need to make advances in experimental and numerical techniques so as to understand the three-dimensional features of tsunami run-up. This research program is a coordinated effort among several researchers to investigate this phenomenon through innovative combinations of modern experimental techniques, mathematical theories and numerical models. Dr. Philip L.-F. Liu at Cornell University and Dr. George F. Carrier of Harvard University are responsible for the theoretical and numerical study; Dr. Harry H. Yeh at the University of Washington is in charge of the small-scale experimental program; and Dr. Costas E. Synolakis of the University of Southern California and Mr. Mike Briggs of the Coastal Engineering Research Center (CERC) of the U.S. Army Corps of Engineers are leading a research team to carry out the large-scale experiments at CERC in Vicksburg, MS. The goals of the program are: (1) To achieve a better understanding of the physical phenomenon and to identify important physical parameters involved in three-dimensional tsunami run-up; (2) to advance the numerical modeling techniques for simulating three-dimensional free surface flows; (3) to develop analytical and numerical solutions for the laboratory experiments; and (4) to generate a data-base of experimental results for future verification of different numerical models. This research program will facilitate and enhance interactions between researchers in universities and various government agencies and laboratories.