This manual is for licensed mental health providers who provide psychotherapy and related services. Treating clients suffering from posttraumatic stress disorder and related disorders can be challenging, even for a seasoned practitioner. This is partially due to the fact that posttraumatic stress disorder is about something. The reasons for your client's distress are known. Your client has experienced trauma, and the symptoms are an expression of, and the result of, the traumatic experience. When a client presents with symptoms of posttraumatic stress, there is always a difficult story waiting to be told. And your client may or may not be ready to tell it. And you, the practitioner, will need to hear the story. This, too, can be difficult. Traumatic experiences may call into question, both for the practitioner and the client, everything they believe to be true: That people are inherently good. That good things happen to good people. That we can protect ourselves and our families from harm. That life is fair. Traumatic experiences happen in spite of us believing that they should not. And more often than not they don't just happen. Much trauma is related to what people do to each other. Children are hurt by their parents. Spouses hurt each other. In other words, there is often an interpersonal component to traumatic experiences. This can make recovery from Posttraumatic stress disorder difficult. If your client has been hurt by someone close, it can be difficult to enter into a new relationship-and that includes the therapeutic relationship. For the treatment provider, this can be frustrating. You may know exactly what you need to do but find that your client can't let her guard down. Also keep in mind that clients who come from historically marginalized populations-such as those subjected to broad-scale, historical trauma-may have suffered relational (and actual) injuries that can make it very difficult for them to believe that any one person or institution can be trusted at all. For mental health professionals, building trusting relationships with clients and knowing which interventions will most benefit them are challenging enough. Helping clients who are also dealing at the same time with chronic conditions such as poverty, violence, and addiction can seem overwhelming. That's especially true for behavioral health service providers who have limited experience. That's why we at OhioGuidestone have developed this series of clinical manuals to help professionals develop their skills while providing effective treatment. OhioGuidestone, the largest community behavioral health organization in Ohio, regularly trains new therapists and other behavioral health interventionists to work with clients who face severe, therapy-interfering challenges. We've brought that experience to these manuals.