The contention that client insight "causes" symptom reduction was examined for 12 clients who completed 20 sessions of psychotherapy. Clients rated target complaints before each counseling session and completed the Important Events Questionnaire (IEQ; A. L. Cummings, J. Martin, E. T. Hallberg, & A. G. Slemon, 1992) after each counseling session. Counselors rated target complaints for their clients after each session. Three judges rated the IEQs using the Insight Rating Scale (IRS; R. W. Morgan, L. Luborsky, P. Crits-Christoph, H. Curtis, & J. Solomon, 1982). Validity of the IRS was established by examining the relationship between IRS ratings, counselor-judged insight, and counts of client insight statements. Regression analyses showed that clients had significant linear increases in insight and significant linear decreases in target complaint distress across the 20 counseling sessions. Time-series analyses showed that increases in insight led reductions in target complaints. These results support the importance of insight for symptom reduction.