Enterprise Research Planning (ERP) software is advertised as the product that will "run the enterprise", improving data access and accuracy as well as enhancing business process efficiency. Unfortunately, organizations often make implementation decisions with little consideration for the maintenance phase of an ERP, resulting in significant recurring maintenance costs. Poor cost estimations are likely related to the lack of an appropriate framework for enterprise-wide prepackaged software maintenance, which requires an ongoing relationship with the software vendor. The end result is that critical project decisions are made with little empirical data, resulting in substantial long-term cost impacts. The product of this research is a framework emerging from an integrated view of diverse theories regarding technology acceptance, information system success, ERP implementations and software project dynamics. Integration of these theories was operationalized via a formal dynamic simulation model that enables theory testing, scenario exploration and policy analysis. In order to provide a triangulated view of the problem, the resulting ERPMAINT1 simulation model was developed by combining and extending existing frameworks in several research domains, incorporating quantitative case study data as well as qualitative and quantitative expert interview data. The ERPMAINT1 model evaluates tradeoffs between different ERP implementation decisions and their impact on post-implementation Total Cost of Ownership (TCO), system acceptance and perceptions of success. The simulation model provides a mechanism to better predict long-term ERP costs, increase communication effectiveness between project stakeholders and improve strategic decision-making. Through model simulations a variety of dynamic insights were revealed that can assist ERP project managers. For instance, simulation showed that upfront investments in mentoring and training translate to long-term cost savings. They also indicated that in addition to customizations, add-ons have a significant impact on TCO. This research provides various contributions and future research opportunities in system dynamics, ERP management, software project management, technology acceptance and IS success in both academic and practitioner settings. It extends existing system dynamics project models and offers a new method to explore Technology Acceptance Models (TAM) and IS Success theoretical frameworks. [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.]