A networked computer system enables one or more transactions to be executed securely. An initiator sends a service request to a control server. The control server creates or selects an existing transaction server for the sole purpose of executing the transaction requested by the service request. If the transaction server is pre-existing, it may be in an inaccessible state and then be made accessible in response to receiving the service request. The control server informs the initiator of the created transaction server. The initiator (and possibly one or more other authorized participants) engages in the transaction with the transaction server, independently of the control server. The transaction server terminates, such as upon completion of the transaction, the expiration of a timeout period, or satisfaction of another server termination criterion. The use of such a one-time transaction server increases security, privacy, and anonymity.