A study tried to determine if development can continue through middle age, if education can stimulate adult development, and, if so, what the contributing factors are. The subjects were 60 men and women who had begun doctoral studies between ages 37 and 48, half of whom had just finished and half of whom had just started. Half of the students were from an array of traditionally structured schools, half from a single school (Fielding Institute in Santa Barbara, California) organized along principles of self-directed learning. All subjects completed the Sentence Completion Test of ego development (SCT), a projective measure that has been used for more than 30 years. Subjects also completed comprehensive questionnaires, and 17 were interviewed in depth. The study found that students in the nontraditional school experienced significant ego growth, whereas those in traditional schools manifested ego regression. Pacing (the exposure to a level of cognitive or moral complexity that is just beyond the student's current developmental level) was found to be a significant factor in ego growth. Unconditional acceptance also was found to be an important element. The study concluded that a learning environment can be designed that will foster not only content mastery and skill acquisition but also human development. (32 references.) (KC)