ABSTRACT We studied longitudinal changes in self-development and psychopathology over a 15.7-month period (SD =4.4 months) in 271 maximum-security prisoners who were participating in either the Transcendental Meditation (TM) program, counseling, drug rehabilitation, or Muslim or Christian groups. f'or each program, new and advanced participants were compared with (a) subjects interested in participating who were delayed from starting, (b) subjects who were not interested in participating, and (c) subjects who dropped out.