The cognitive therapies (e.g., Beck, 1976; Ellis, 1970; Meichenbaum & Cameron, 1973; Mahoney & Arnkoff, in press) attempt to alter what the client thinks and thus to produce significant affective or behavioral change. Cognitive therapy theory states more or less explicitly that particular frequently occurring cognitions elicit particular undesirable behaviors or affective states, and that therapy should aim at reducing the frequency of the particular cognitions involved. The assessment of the cognition frequencies has usually been by the client's retrospective report (e.g., " I don't think about it as much as I used to") or ex hypothesi by counting the "resultant" affective or behavioral undesirable states. Hurlburt (1976, in press) has demonstrated the unreliability of retrospective reports of cognitive frequencies, and since the circularity of the latter counting method prohibits applying that evidence to the cognitive therapy theory, we are at this time unjustified in uncritically accepting the reduction-of-frequency-of-undesirable-cognitions explanation for the efficacy of cognitive therapy (Mahoney, 1977, p. 10). Hurlburt proposed cognition sampling as a means of making unbiased estimates of cognitive frequencies, and thus provided a way of bringing reliable, noncircular evidence to bear on the important issue of the cognitive frequency-affective/behavioral relationship. The present case applies Hurlburt's method for the first time to a clinic client, and serves as a hueristic for further research as well as a model for clinical application. The method uses