This text integrates the theory and practice of learner-based assessment. Written in response to two recent movements in language teaching--learner-centered teaching and a renewed interest in authenticity in language testing--it examines the relationship between the language learner and language assessment processes, and promotes approaches to assessment that involve the learner in the testing process. Particular attention is given to issues of reliability and validity. Grounded in current pedagogical applications of authentic assessment measures, this volume is intended for and eminently accessible to classroom teachers and program directors looking for ways to include their students in the evaluation process, graduate students, and professional language testers seeking authenticity in assessment and desiring to create more interactive evaluation tools.