NASA's budget has decreased, and information systems (IS) are a large part of the processes of exploration today. IS and technology entail committing millions of dollars, so the usability, success, and return on investment (ROI) have a direct impact on the NASA budget. Two strong determinants of successful information systems are usability and the user's continuance intention. A quantitative methodology design, utilizing the System Usability Scale (SUS) was used in this study to measure satisfaction indicating the existence of usability and a post acceptance tool which determines continuance intention indicating systems' usability. The Likert-type scale survey was given to 114 participants working on a NASA payload integration contract in the management, engineering, and operations areas. Structural equation modeling tested the five hypotheses and determined if there was a relationship between perceived usefulness, confirmation, satisfaction, and continuance intention. The SUS measured the existence of usability from the users' perspective. The expectation-confirmation theory (ECT) and the continuance intention model using structural equation modeling (SEM) quantitatively measured if there was a relationship between perceived usefulness, confirmation, satisfaction, and continuance intention. This study supported ECT's suggestion that satisfaction (R² = .773) with IS use is the strongest predictor of continuance intention and, with perceived usefulness (R ² = .504), is a slightly less, but still significant, indicator of continuance intention. Intention to continue IS use is predicted by satisfaction (β = 0.24) and perceived usefulness (β = 0.684). Confirmation, perceived usefulness, and satisfaction are salient determinants of continuance intention. The measurement of satisfaction and user's continuance intention with IS from a user's perspective indicated participants in the study are not satisfied with the present IS; therefore, usability does not exist. Since ROI is higher on system enhancement than new systems, it is recommended enhanced IS will maximize user satisfaction, continuance intention, and ROI. Future research should broaden the user-satisfaction-continuance link to IS success through the use of pre and post acceptance in the studies. Future studies' focusing on usability and the users' perspective of IS will result in better ROI and improved efficiency in organizations, private and governmental.