Michigan is designing a new accountability system that combines high standards and statewide testing within a school accreditation framework. Sound assessment techniques are critical if the accountability system is to provide relevant information to schools and policymakers. One important component of a sound assessment system is measurement of student learning during the school year. Two primary ways of assessing student learning are absolute measures of achievement and value-added assessment. Value-added assessment attempts to distinguish learning that occurs because of factors that the school can control from learning that is affected by uncontrollable factors. By measuring the value that was added to a student's achievement by a school, rather than by factors outside of the school's control, a school can be held accountable for the performance of students in that building. Absolute measures of student achievement such as average scores provide a snapshot of learning but do not allow separation of school and non-school influences on student achievement. This paper is divided into three sections. Section I examines the background of value-added assessment and discusses why it should be part of Michigan's accountability system. Section II compares the implementation of value-added testing in several states and examines similarities and differences between the models. Section III outlines steps that would be necessary to implement a value-added system in Michigan. Michigan has recognized that its current accountability system is inadequate. The state has begun the process of developing an accountability system that includes construction of a Single Record Student Database and the development of an annual testing program, use of multiple indicators in evaluating student progress, and instituting a set of rewards for schools where students meet state goals for progress. While there is no one best system of accountability, the fairness of the system must be a key concern. When educators perceive a system as fair, they are more likely to accept and support the system. When teachers are provided with fair assessments of student achievement, they can use the information in a thoughtful manner to reflect on and improve their instruction. An important component of any fair accountability system is the inclusion of a value-added testing program. Value-added testing responds to the state superintendent's request that, before implementing any new program, the question is asked, "What does this do to help teachers teach and students learn?" By providing teachers, parents, legislators, and the general public with a fair measure of student learning, value-added testing helps to ensure that the accountability system is a tool for improved teaching and learning. (Contains 2 footnotes and 1 table.)