As psychology has recognized the rights of clients and subjects to exercise a rational, voluntary choice about participation in research, assessment, and treatment, the use of written informed consent forms has increased. A sample of 196 psychologists in private practice were mailed questionnaires which examined their use of, and rationale for, written consent forms; the information covered by such forms; and the readability of the forms. Subjects returned completed questionnaires and copies of their consent forms which were then scored for readability. Of the 104 respondents, 30 reported using written consent forms. Users of written forms were significantly younger than non-users; there were no differences in frequency of use due to sex or theoretical orientation. The major reason cited for not using forms was a preference for verbal agreements. The content of the forms dealt primarily with issues regarding fees, and not with information which satisfies the requirements of informed consent, such as risks of treatment and alternative treatments. The average readability for the returned consent forms was "difficult," equivalent to an academically-oriented magazine. The findings suggest that therapists need to evaluate their practices regarding informed consent in order to increase clients' autonomy and their understanding of information provided. (NRB)