Abstract: One disclosed embodiment for creating a composite scene passcode comprises presenting a system-generated composite scene passcode to a user, allowing the user to generate a composite-scene passcode by selecting one scene element per scene dimension, or allowing the user to enter an alphanumeric password that encodes the composite scene passcode. Certain embodiments also comprise combining the passcode with an alphanumeric password. The composite scene may be two dimensional, three dimensional, or greater than three dimensions, and/or the scene may be animated. A computer system using a composite scene passcode also is disclosed. One embodiment of the system comprises a display for displaying a composite scene passcode or plural scene dimensions for generating the composite scene passcode. Authentication may comprise using scene elements arranged categorically and requiring the user to select the correct scene element from among distracter elements within the same category.