A method comprises making a set of personal profiles available, from at least one buy-side user to at least one sell-side user, each personal profile in the set of personal profiles including a first set of first values for a plurality of information fields, the plurality of information fields relating to commercial transactions. Based upon the at least part of the set of personal profiles, the method receives a request to enter into a trusted relationship from the at least one sell-side user at the at least one buy-side user, and receives a set of trusted relationship information from the at least one sell-side user at the at least one buy-side user. The method sends the set of trusted relationship information, from the at least one buy-side user to the at least one sell-side user. The relationship includes a variable level of trust which affects the amount of infrastructure functionality available to one or more users and wherein the variable level of trust comprises a first level of trust and a second level of trust and wherein the first level of trust is set by the at least one buy-side user and the second level of trust is set by the at least one sell-side user.