This research investigates the phenomenon of budgeting practices in the Tanzanian Central Government. It seeks to understand how budgeting systems under the New Public Management (NPM), World Bank- and IMF-exhorted systems were adopted and implemented. There were several motives for this research: the significance of budgeting in financial management, the sparsity of empirical studies on NPM in developing countries, and a call for an understanding of the local contexts of the country and an evaluation of the reforms themselves. Additionally, the complexity of NPM reforms and the mixed results of previous empirical studies, indicated the need for a more appropriate methodology. The study adopts interpretive research and executes a grounded theory strategy. It develops a substantive grounded theory on budgeting practices and a formal grounded theory on accounting changes in organizations (Glaser and Strauss, 1967; Strauss, 1987). Fieldwork was undertaken in three Tanzanian Ministries. Struggling for conformance is the central phenomenon of the substantive and the formal grounded theory. The substantive grounded theory explained a process through which the Tanzanian Central Government actors were determined to implement budgetary reforms, despite difficulties. Struggling for conformance was illustrated by the establishment of rhetorically applied (rhetorical) rules and regulations, followed by budgeting attempts and games in their implementation, due to the uncertain environment, complex budgeting systems, the donors‟ influence, and cultural and administrative practices. The process of struggling for conformance had positive and negative impacts on budgeting operations and budgeting allocations. The formal grounded theory proposes that organizations adopt and implement accounting changes in order to achieve legitimacy, efficiency and self-interests. Rhetorical rules on accounting changes are established and implemented through accounting attempts and games, which may reveal the coexistence of instrumental and ceremonial aspects of accounting (Covaleski and Dirsmith, 1991), and even fulfill individual, rather than organizational, interests (strategic deterioration). Struggling for conformance is caused by conflicting and enabling power, complex rules, and a fragmented environment. Its consequences reflect the extent of the acquisition of efficiency and legitimacy. This research contributes to the limited amount of empirical accounting research on NPM in developing countries, to grounded theory and interpretive accounting research, and to the expansion of New Institutional Sociology. It further provides a framework of struggling for conformance, which produces possible explanations for the complexities of budgetary and NPM reforms, the adoption and implementation of accounting changes in organizations, and loose coupling