The present invention relates to the field of therapeutic methods to screen for compounds on the basis of their ability to influence Wnt activity. The screening process is applied to both a physical library of a series of compounds and a virtual library of compounds that affect Wnt activity. In one aspect, the virtual screening process could be carried out where a permutational library of small peptides is substituted for the small organic molecules. The inventive methods may be used to empirically test for effects on Wnt activity and may also be applied to any pair of proteins involved in protein-protein interactions.