How does defense against the perception of traumatization restrict memory ability, and what consequences must be drawn for therapy as a result? These questions have not been systematically answered so far. The author examines in this work the different forms of defense against the perception of traumatization that are employed, the functions they serve, and the psychological effects that can be expected due to specific defense mechanisms. Answering these questions has immediate consequences for therapy and assessment. Based on the research findings from qualitative case studies, treatment recommendations are developed on how to address issues related to memory ability concerning traumatic events in trauma therapies.