While private sector organizations have implemented enterprise resource planning (ERP) systems since the mid 1990s, ERP implementations within the public sector lagged by several years. This research conducted a mixed method, comparative assessment of post "go-live" ERP implementations between public and private sector organization. Based on a survey of 194 ERP adopting organizations and supported by four interviews of senior IT executives/leaders within the public and private sector, the research identifies that differences exist in governance design, timeline to accept and timeline to extend baseline ERP implementations between public and provide, but differences do not exist in how public and private sector organizations design sustainment structures, in the importance of governance and sustainment structures within public and private sector organizations and in the relative importance of governance, sustainment and extension to driving organizational transformation. Continued engagement with senior leaders and effective training focused on business processes are critical components following ERP implementation that aid continuing organizational transformation. [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.]