BRITE is a database of binary relations for computation and comparison of graphs. It contains diverse sets of binary relations, including the generalized protein-protein interactions that underlie the KEGG pathway diagrams, systematic experimental data on protein-protein interactions by yeast two-hybrid systems, sequence similarity relations by SSEARCH, expression similarity relations by microarray gene expression profiles, and the cross-reference links between database entries. This is a preliminary version of BRITE for simple retrieval of partners.