The effect of type and amount of instruction on the problem solving behavior of novice Macintosh users were examined. Forty-eight naive users participated in one of four conditions; no instruction, self-paced written instruction on either basic mouse skills, or on basic mouse and file manipulation skills, or animated instruction on basic mouse and file manipulation skills. Subjects then completed mouse tasks, file manipulation tasks, and transfer tasks. Results indicated that the Macintosh is not a "walk-up-and-use" computer as the no instruction condition was slower and less successful at completing the tasks than all other conditions. The mouse skills condition completed more tasks, and were somewhat faster at completing the file manipulation and transfer tasks than the no instruction condition. Comparison of the animated condition and the equivalent written condition indicated no advantage for animation, and both conditions showed high levels of transfer. Analysis of individual tasks showed some evidence of the problem solving heuristic of label-following for the no instruction and mouse skills conditions. Direct manipulation interfaces, like the Macintosh, which allow the user to interact directly with graphical representations of system objects, are generally considered advantageous for users for a number of reasons [l-41. First, allowing the user to interact directly with system objects results in a more active engagement with the system, rather than a passive involvement. Second, direct manipulation interfaces reduce the cognitive distance between what the user intends to accomplish and the actions required to accomplish those intentions. Novices, in particular, seem to perform more efficiently when using a direct manipulation interface as compared to an indirect, command-language based interface [5-71. While this evidence and rationale indicate advantages for direct manipulation interfaces, difficulties in using direct manipulation interfaces still exist. Early research evaluating the effectiveness of the Lisa computer, a predecessor to the Macintosh, 29 0 1995. Baywood Publishing Co., Inc.