Approved for public release; distribution in unlimited. / This thesis examines the effectiveness of the Indoor Simulated Marksmanship Trainer (ISMT) as a tool to train shooters in the fundamentals of marksmanship. Key concepts explored in the research are verification of skills transfer resulting from practice and the predictive value of simulated performance to proficiency at real task performance. There was no statistical difference in the scores of recruits trained in the ISMT versus a control group that was not trained in the ISMT. Scores on simulated firing were not a strong predictor of live fire performance. In a second experiment subjects were evaluated on their proficiency and improvement during un-coached practice at the task of simulated precision fire on a target at a simulated known distance of 300 yards from the shooters. After comparable amounts of practice in the ISMT, subjects who had not previously received formal marksmanship training failed to demonstrate levels of proficiency comparable to those subjects who had previously received formal marksmanship training in the military. Consequently, the research found no evidence to suggest the ISMT qualifies as a black box training apparatus capable of imparting skill through practice without the added presence of expert instruction or an existing knowledge of marksmanship techniques. / Major, United States Marine Corps