A computer-implemented system stores profiles for parties to the negotiation, each profile specifying values for one or more parameters negotiated, the values reflecting a desirable outcome of the negotiation for the associated party. A matching server accesses an offer from a first party containing values for one or more of the parameters negotiated and computes a distance between the offer values and the profile values of a second party. If the distance is acceptably small, the server causes the offer to be accepted by the second party to conclude the negotiation. If the distance is not acceptably small, the server automatically modifies one or more values in the offer such that the distances between the modified offer and the profiles of the first and second parties are acceptably small simultaneously and causes the modified offer to be accepted by the first and second parties to conclude the automatic negotiation.