Rounding the corner on the design of new teacher-evaluation plans, states and districts are beginning to wrestle with the significant technical and logistical hurdles for transforming their blueprints into reality. In the coming months, more states--especially those that won grants through the $4 billion federal Race to the Top initiative--are expected to put out requests for proposals for such details as overhauls to the data systems that store student and teacher information; the provision of "value added" analyses of teacher performance; and the reporting and professional development that help teachers and principals use the information from the systems. In sum, states and districts must construct integrated systems for teacher-performance management--no small challenge in a field in which few good examples exist. The situation is complicated by the fact that the marketplace of contractors, vendors, and providers that states must rely on to fulfill their plans is still evolving. To give just one example, many of the technical experts on such elements as the statistical modeling of value-added teacher estimates don't work for traditional education publishers or test companies, but for organizations now primarily known for research or program evaluation.