different configurations. In each session, the participants were shown four different configurations drawn on a piece of paper and were asked to use the puzzle to reproduce the configurations while they were being timed. The first and third session of the experimental condition were identical to control, but in the second session the participants in the experimental condition were given a dollar for completing each puzzle within time. During the middle of each session, the experimenter left the room for eight minutes and the participants were told that they were free to do whatever they wanted during that time, while the experimenter observed during that period. The amount of time spent working on the puzzle during the free choice period was used to measure motivation. As Deci expected, when external reward was introduced during session two, the participants spent more time working on the puzzles during the free choice period in comparison to session 1 and when the external reward was removed in the third session, the time spent working on the puzzle dropped lower than the first session. All subjects reported finding the task interesting and enjoyable at the end of each session, providing evidence for the experimenter's assumption that the task was intrinsically motivating for the college students. The study showed some support of the experimenter's hypothesis and a trend towards a decrease in intrinsic motivation was seen after money was provided to the participants as an external reward. Experiment II The second experiment was a field experiment, similar to laboratory Experiment I, but was conducted in a natural setting. Eight student workers were observed at a college biweekly newspaper. Four of the students served as a control group and worked on Fridays. The experimental group worked on Tuesdays. The control and experimental group students were not aware that they were being observed. The 10-week observation was divided into three time periods. The task in this study required the students to write headlines for the newspaper. During "Time 2", the students in the experimental group were given 50 cents for each headline they wrote. At the end of Time 2, they were told that in the future the newspaper cannot pay them 50 cent for each headline anymore as the newspaper ran out of the money allocated for that and they were not paid for the headlines during Time 3. The speed of task completion (headlines) was used