Language testing is an area of applied linguistics that combines the exercise of professional judgment about language, learning, and the nature of the achievement of language learning with empirical data about student performance and, by inference, their abilities. The relationship between judgments and empirical data in language testing is examined through three studies. The first investigates language professionals' judgments about test content and the skills and abilities supposedly being tested by certain test items and compares them with test results and the attitudes of test-takers. The second study compares the judgments that experienced test writers and scorers make about item and test difficulty and compares them with item results. The third study gathers judgments from language testers and teachers about standards of performance of a given population in a standard-setting exercise aimed at determining grade boundaries for a public examination. The implications of the findings are discussed. (Author/MSE)