This document discusses principles of effective language assessment. It defines language assessment as evaluating language proficiency or ability. Effective assessment should be aligned with learning goals, reflect real language use, and be fair and reliable. There are different types of language assessment, including formative to provide feedback, summative for evaluation, and diagnostic for identifying strengths and weaknesses. Key considerations for effective assessment include validity, reliability, authenticity, transparency, and fairness. Assessment is important for learners and educators to evaluate proficiency and inform instruction.