Three groups of long term meditators, ranging from 1.33 years to 8.75 years, were given a four quadrant mode of control inventory, reflecting a control model of psychological health. A linear relationship between length of practice and positive modes of control, particularly quadrant two (positive yielding) was hypothesized. As expected, the group which had practiced the longest had the highest quadrant two score and the most psychologically healthy profile. However, the relationship was curvilinear, not linear. These subjects then attended either a 2 week or a 3 month intensive retreat and were assessed immediately following the retreat (post test 1); after one month (post test 2) and after six months (post test 3). As hypothesized, the retreat intervention had the largest and most positive effect on quadrant two (positive yielding) from pretest to six month follow-up; and there were larger increases in quadrant two for the three month retreat than the two week retreat. Findings for overall satisfaction, self-control, and gender differences are also reported, and the article concludes with a discussion of the study's limitations and suggestions for future research.