We studied 814 client laughter events nested within 330 sessions nested within 33 clients nested within 16 therapists at one community clinic in which doctoral student therapists provided psychodynamic psychotherapy to adult community clients. Each laughter event in Sessions 1 to 5 and 16 to 20 was rated for cheerfulness, politeness, reflectiveness, contemptuousness, and nervousness. Across all clients, there was an average of about one laughter even per session. The average laughter event lasted 3.5 seconds, and was characterized primarily by politeness and reflectiveness. Overall amount of client laughter and the characteristics of client laughter did not change across sessions. Most of the variance in the laughter characteristics was at the session level, with less variance attributable to clients and therapists. When client attachment avoidance was high, laughter was less cheerful and more contemptuous. When client attachment anxiety was high, laughter was more nervous. Sessions with more reflective laughter were evaluated more positively by clients, and therapists whose clients had more reflective laughter had more positive client session evaluations. Furthermore, within a therapist’s caseload, clients with the most nervous and contemptuous laughter evaluated sessions most positively. Implications are discussed.