The New Public Management (NPM) reform in the late twentieth century around the globe incites the need for increased accountability and transparency at governmental level both central and local. The International Public Sector Accounting Standard Board (IPSASB) has developed a set of reporting standards called IPSAS to assist public sector improving its financial reporting. Many countries have opted for the NPM including Indonesia in 1999 which came up with a decentralisation programme and New Public Financial Management. The latter dealt principally with better accounting and reporting including the adoption of IPSAS on a gradual term. It took Indonesia half a decade to move towards the adoption of modified cash basis accounting or cash towards accruals accounting (CTA). In 2008 all local governments were expected to adopt IPSAS accruals but that was not realised until 2010. The government had to pass Law No. 71/2010 requiring all government bodies to prepare accruals based financial statements. However, that was again not achievable until 2013. The Ministry of Home Affairs (MOHA), to whom central government has delegated power to monitor local government accounting, passed a Decree No.64/2013 enforcing municipalities and cities to pass a regulation to make IPSAS adoption and implementation mandatory. They were given a time frame to put this in action but not all local government bodies have adopted and implemented IPSAS and those who have, may also not fully implementing them, thus raising a question as to their harmonization of practices. This thesis investigates the adoption and harmonization of International Public Sector Accounting Standards (IPSAS) in Indonesian local government financial reporting. It focuses on mainly municipalities and cities. It posits that there are a number of drivers behind the adoption and harmonization with IPSAS in local government. Drawing from institutional theory, the impact of the isomorphic pressures on IPSAS adoption by the Indonesian’s municipalities and cities is determined. Then drawing from stakeholder salience theory, the thesis investigates the determinants of accounting harmonization with IPSAS. This study uses a sample of 171 municipalities and 34 cities from a total population 515 and secondary data to conduct this research. Using a variety of regression techniques the thesis has assessed the effect of isomorphic pressures on the extent and speed of IPSAS adoption and stakeholders’ salience influence on the extent and level of harmonization of accounting systems and practices with IPSAS in local government. The study finds that the three isomorphic pressures (coercive, mimetic and normative) influenced the adoption of IPSAS in Indonesia. Religion is negatively associated with IPSAS adoption and the reason is due to Indonesia being much more of Islamic faith, hence preference for Islamic accounting. The time taken to adopt IPSAS also varies between municipalities and cities. Especially municipalities that have been in existence for a long time is more reluctant to the change. As a result, there are 15 municipalities and 3 cities that were early-adopters and 68 municipalities and 13 cities as late-adopters of IPSAS. As regards harmonization, there are still some significant differences between Indonesian Government Accounting Standards and IPSAS. The average harmonization score is only 52.83%. Stakeholders’ power/legitimacy and urgency also influence harmonization of accounting in the local government of Indonesia. These findings are important information for professional accounting bodies, regulators, Audit Supreme Office, policy-makers including politicians as well as local and foreign aid agencies to make decision. Regulators will use the findings to identify where adoption is problematic and why, whereas the Audit Supreme Office will use the findings as a reference for future audits. Politicians including policy makers will be able to use the findings to determine the effectiveness of the policies related to accounting innovation in local government. Foreign aid agencies like the World Bank will be interested to know whether Indonesia has met its commitments to IPSAS adoption. This thesis is the first that informs the literature on velocity of IPSAS adoption and harmonization of accounting with IPSAS in the Indonesian local government sector.