The traditional reliability coefficient and standard error of measurement are not adequate measures of reliability for tests used to make pass/fail decisions. Answering the important reliability questions requires estimation of the joint distribution of true and observed scores. Lord's "Method 20" estimates this distribution without the deficiencies of other methods. New output formats condense the estimated distribution into readily usable information, including a 2 x 2 contingency table, conditional true-score distributions, and an index of decision-making efficiency. Examples are appended. (Author/CTM)