1. A method for bidirectional matching between parties belonging to a first group and parties belonging to a second group, the method including the steps of: (a) collecting from the parties data indicative of criterion responses for a plurality of criterions, wherein each criterion has a pre-assigned baseline rating score; (b) in respect of at least a selection of the criterion responses, determining preferential rating scores, (c) on the basis of a criterion match determination protocol, processing the data indicative of criterion responses, thereby to identity criterion matches between parties belonging to the first group and parties belonging to the second group; and (d) determining, for each criterion match, a criterion match rating based on a function of the baseline rating score and, where determined, the preferential rating score or scores.