Reliability in assessment refers to the consistency and dependability of test scores or evaluation results. A reliable assessment produces stable and consistent results over repeated administrations and across different evaluators. In language testing, reliability ensures that a test accurately measures a learner's ability and provides trustworthy data for making educational decisions. Factors that contribute to reliability include clear and consistent scoring criteria, well-designed test items, and standardization of test administration procedures. Reliable assessments are essential for ensuring fairness and validity in evaluating language proficiency.