In the frame of the research program we have investigated graph products, their invariants and related problems.We have studied median graphs, in particular the recognition problem for these graphs. We have considered several classes of graphs that are naturally connected with the median graphs: isometric subgraphs of hypercubes, semi-median graphs, quasi-median graphs and isometric subgraphs of Hamming graphs. Among others we have applied metric graph theory in chemical graph theory for calculations of different topological invariants. Graphs with gated cliques and the determination of the smallest number of linear forests were treated as well. In the area of computer mathematics we were working on developments of fast algorithms for recognition important graph classes and on the problems connected with generalizations of the classical Tower of Hanoi problem. One of the primary goals of the program was a monograph that covers graph products and related topics. We have published all together 56 scientific papers, among them 44 papers in the journals that are covered by the JCR. We have presented our results on several international conferences and gave invited lectures at several conferences and universities. The monograph W. Imrich, S. Klavžar, Product Graphs: Structure and Recognition, was published in 2000 at one of the most renowned scientific publishers John Wiley & Sons in New York. We were cooperating with many established scientists from abroad, in particular with W. Imrich from Austria, H.M. Mulder from The Netherlands, I. Gutman from Serbia and Montenegro, I. Ivanšić from Croatia, M. Mollard and S. Gravier from France.