The Technology Acceptance Model (TAM) predicts the user acceptance of end-user applications by specifying causal relationships among belief and attitudinal constructs that subsequently influence usage behavior. Although the perceived usefulness and perceived ease of use constructs have received a great deal of attention in MIS literature, very few follow-up studies have used the original TAM constructs. Moreover, the various studies investigating TAM use different measurement items, or factors, to assess the belief constructs. In this TAM study, the impact of external variables affecting usage behavior is examined. The results suggest that the impact of the external variables on usage behavior is not fully mediated by the belief constructs.