Humans are not very good at detecting deception in normal communication. One possible remedy for improving detection accuracy is to educate people about various indicators of deception and then train them to spot these indicators when they are used in normal communication. This paper reports on one such training effort involving over 100 military officers. Participants received training on deception detection generally, on specific indicators, and on heuristics. They completed pre- and post-tests on their knowledge in these areas and on their ability to detect deception. Detection accuracy was measured by asking participants to judge if behavior in a video, on an audiotape, or in a text passage was deceptive or honest. Trained individuals outperformed those who did not receive training on the knowledge tests, but there were no differences between the groups in detection accuracy. In addition, individuals who received training using specially developed software did as well as individuals who were trained by lecture or by lecture and software in combination, for both knowledge and detection accuracy.