A system and method for a consumer to order goods and/or services from a vendor through use of an instant messaging service. The consumer initiates an instant message communication link between the consumer and the vendor by using the vendor's screen name which has been added to the consumer's list of contacts and sending an initiating message. Software resident on the vendor's computer responds to initiation of the instant message communication link by supplying a list of good and/or services to the consumer. The consumer can order from the list of goods and/or services while concurrently communicating with the vendor. An order identification number is created each time an order is placed which includes information from the consumer's screen name, the vendor's screen name and software generated information. The order identification number uniquely identifies the order and is used only once.