A method and system for strong, convenient authentication of a web user makes use, for example, of a computing device, such as a user's personal computer (PC), coupled over a network, such as the Internet, to one or more servers, such as the host server of an authenticating authority, as well as one or more databases of the authenticating authority. The authentication process is broken into three phases, namely a registration phase, an enrollment phase, and a transaction authentication phase, with each phase being less intrusive and less secure than the preceding phase. In the registration phase, an authenticating authority registers the user based upon identification of the user using a strong authentication technique and provides an authenticating token to the user, which can be used in the enrollment phase to enroll one or more user devices for the user. Thereafter, in the transaction authentication phase, the authenticating authority can authenticate the user for a transaction based on presentation by the user of a user password via the enrolled user device.