Educational and economic research shows that investing in school preparedness for low- income children prevents needless public spending and produces payoffs in K-12, government programs, and the private sector. Conversely, not investing in or cutting programs that produce school readiness results in increased spending and lost benefits for: (1) Schools; (2) Taxpayers; (3) The public; and (4) The economy. This study estimates the current cost savings and revenues to Michigan generated from the investments in school readiness over the past 25 years, the cost burden to Michigan when children are not fully prepared at kindergarten entry, and the additional benefits that could be realized if Michigan were to expand its investment in school readiness to all educationally disadvantaged children. Findings of this study reveal that Michigan has made substantial investments in school readiness over the past 25 years and, accordingly, has reaped the benefits of adequately preparing many children for school success, resulting in more than a billion dollars in annual savings and revenues. If the state's current investments in school readiness were discontinued or reduced, these annual savings and revenues would subsequently erode, causing a significant negative impact on the State of Michigan's future annual budgets and overall economy. Conversely, those benefits will rise if the state sustains its current level of investment and will increase exponentially as a result of increased investment in the Great Start Readiness Program, Great Start system, and other high-quality and comprehensive programs that promote early educational preparation. Appendices summarize the estimated effects and net benefits of early childhood education with regard to special education and grade repetition and also shows Michigan K-12 Enrollment Fall-2008. (Contains 14 figures and 2 footnotes.) [This paper was prepared for the Early Childhood Investment Corporation. For the executive summary, see ED511603.]