Ten conditions of trust were suggested by 84 interviews of managers, and two previous studies of managerial trust. Statements made in the interviews and the studies were used to develop a content theory of trust conditions and derive scales measuring them. The scales were generated with an iterative procedure using a total of 1531 management students. The scales were assessed for homogeneity, reliability, and validity with several samples: 180 managers and 173 of their subordinates, 111 machine operators, and four different samples of management students (n = 380, n = 129, n = 290, and n = 132). Construct validity was supported by showing that the scale measures behaved as hypothesized with respect to measures of other variables, a manipulation of expectations, and the reciprocity of trust in vertical dyads. © 1991, Sage Publications. All rights reserved.