To determine whether preservice teachers would demonstrate a significant change in level of teacher enthusiasm after participating in a training intervention on teacher enthusiasm, and whether these same preservice teachers could maintain the increased level of teacher enthusiasm three weeks after termination of training, twenty preservice teachers were randomly assigned to either an experimental training group or to a control group. The experimental group was trained to increase their level of teacher enthusiasm through class discussions, peer teaching, and microteaching with public school children. Eight teacher behaviors were identified as descriptors of teacher enthusiasm: (1) vocal delivery; (2) eyes; (3) gestures; (4) movements; (5) facial expression; (6) word selection; (7) acceptance of ideas and feelings; and (8) over-all energy. Data were gathered on the eight teacher characteristics by videotaping the experimental and control groups before and three weeks after the training intervention. Two trained observers rated each of the video tapes on a 5-point scale without knowledge of which preservice teachers were in the experimental or control groups or whether the taping was pre- or post-training. Analysis of the data indicates that the overall performance of the experimental group significantly increased after training and that each of the variables contributed significantly to this increase. The results, therefore, support the theory that it is possible to train a preservice teacher to increase his level of enthusiasm as described by the eight variables. (MM)