Breath-holding has been discussed in the professional literature as a technique for provoking symptoms in various anxiety disorders, but its sometimes paradoxical effects may also be used as a mode of treatment to reduce anxiety. The process of inducing endogenous CO2 accumulation by holding one's breath for varying amounts of time has helped to reduce anxiety in cases involving obsessive-compulsive disorder, shy bladder syndrome., and, in some circumstances, anxiety-induced nausea. The following article addresses the effects of breath-holding and the disorders with which the technique may prove to be effective. Two case vignettes are used to illustrate the use of breath-holding. The article also considers the issue of whether or not breath-holding has been underutilized as an affective technique for a number of psychiatric disorders. Future directions for research in this area are also discussed.