This report was commissioned by the Connecticut Coalition for Achievement Now (ConnCAN) and focuses specifically on the performance of charter schools in Connecticut. Performance gains made by charter schools on standardized tests relative to gains made by traditional public schools are examined. Also, a brief analysis looks at the extent to which charter schools have met their self-specified goals and objectives. Connecticut administers two standardized tests to all public schools. The Connecticut Mastery Test (CMT) is used in grades 4, 6, and 8 and covers reading, writing, and mathematics. The Connecticut Academic Performance Test (CAPT) is administered to 10th graders and covers reading, writing, mathematics, and science. This technical report explains in detail the design and methods used for the study which included both cohort and trend analyses. The positive results in Connecticut are likely due to the unique nature of this reform. Compared with other states, Connecticut exercises more rigor in approving schools to operate and in overseeing charter schools. The closure of a number of struggling charter schools has helped lift the aggregate results of the charter schools. While generalizations cannot be made across states, lessons certainly can be shared from this charter school reform to reforms in other states. Appended are: (1) Connecticut Mastery Test Results for Connecticut Charter Schools; (2) Connecticut Academic Performance Test Results for Connecticut Charter Schools; (3) Comparison of Characteristics of Charter School Students with Host Districts, 2003-04; (4) Results from Trend Analysis on the CMT Using Percent Meeting State Standards; and (5) Results from the Trend Analysis for the CAPT Using Percent Meeting State Standards.