Do you want to use bibliotherapy with clients but wonder about the size and mechanism of effectiveness? The authors report a meta-analysis of 29 outcome studies of cognitive forms of bibliotherapy for depression. Seventeen studies with stronger research designs (pretest–posttest waiting list control group) yielded a respectable effect size of 0.77, considered the best estimate of effect size from this study. This result compares favorably with outcomes from individual psychotherapy. In light of the substantial positive effects associated with bibliotherapy for depression, the authors discuss clinically relevant questions related to the use of cognitive bibliotherapy. These include why practitioners might consider the use of this technique, which individuals can benefit from this approach, and how professionals can structure care.