Education programs across 19 states are piloting a performance-based assessment for teacher-candidates that potentially could serve as a common prelicensing measure for new teachers. Based on a test in use in about 30 education schools in California, the Teacher Performance Assessment includes a "teaching event" requiring teachers to extensively document and submit for review artifacts of their planning, instruction, and ability to assess and respond to student needs. Five of the states taking part in the work-- Massachusetts, Minnesota, Ohio, Tennessee, and Washington--have committed in legislation to use a performance-based licensing test, and officials have signed memoranda of understanding agreeing to adopt the assessment if it proves to be technically valid and reliable. Supporters of the initiative see in the work an opportunity to focus on classroom-based effectiveness at the precertification benchmark--an area that has not received much attention as policymakers tackle the tenure-granting and annual evaluation processes.