Technological devices are ubiquitous in nearly every facet of society. There are substantial investments made in organizations on a daily basis to improve information technology. From a military perspective, the ultimate goal of these highly sophisticated devices is to assist soldiers in achieving mission success across dynamic and often chaotic environments. Since mission success is often dependent on the interaction between the soldier and the device, it is critical for designers to understand this unique interaction. Although numerous usability studies have been conducted, there has been little research in exploring how individual differences influence cognitive performance. Additionally there has been an identified need to account for the evolving military population specifically in regards of technology acceptance and age. This research adjoins Bandura's Social Cognitive Theory (SCT) and usability literature to develop a conceptual framework with supporting hypotheses. Results from an empirical analysis support the majority of the research hypotheses. As suggested by SCT, high computer self-efficacy was positively related to cognitive performance and mission success. Furthermore, this research confirmed the relationship between age and computer self-efficacy. These results encourage the analysis of these constructs and their effects on technological use. By gaining knowledge of these relationships, this research can further enhance human performance models through the development of socio-cultural moderators. Results of this work will be used in the creation of guidelines to support tool development in support of soldier/commander decision-making. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]