257 Trauma survivors are a unique population of clients that represent nearly 80% of clients at mental health clinics and require specialized knowledge on behalf of counselors. Researchers and trauma theorists agree that, with the exception of dissociative identity disorder, no other diagnostic condition in the history of the Diagnostic and Statistical Manual of Mental Disorders (DSM) has created more controversy with respect to the boundaries of the condition, diagnostic criteria, central assumptions and clinical utility than post-traumatic stress disorder. However, this mutable conceptualization of trauma and its aftermath have considerable implications for counseling practice. With the recently released ffth edition of the DSM (DSM-5), the defnition of trauma and the diagnostic criteria for post-traumatic stress disorder have changed considerably. This article highlights the changing conceptualization of trauma and how the DSM-5 defnition impacts effective practices for assessing, conceptualizing and treating traumatized clients. Keywords: trauma, post-traumatic stress disorder, PTSD, DSM-5, diagnostic, clinical utility Nearly 80% of clients seen in community mental health clinics have experienced at least one incident of trauma during their lifetime, representing roughly fve out of every six clients (Breslau & Kessler, 2001). Over the past 15 years, between increases in school and community violence in the United States and unrelenting wars overseas, overt exposure to traumatic events has become an epidemic. Such events affect individuals across the life span and precipitate numerous diagnoses within the Diagnostic and Statistical Manual of Mental Disorders (DSM), most notably post-traumatic stress disorder (PTSD; Breslau & Kessler, 2001). Survivors of trauma are a unique population of clients who require specialized knowledge and multifaceted considerations on behalf of counselors (Briere & Scott, 2006). The Council for Accreditation of Counseling and Related Educational Programs (CACREP) reiterates across both master’s and doctoral training levels the importance of understanding the implications of trauma theory, research and practice in counselor preparation and ultimately practice. CACREP (2009) standards incorporate trauma training within all eight core curricular areas of demonstrated knowledge and within each core counseling track. Section II, Professional Identity, says that counselors should understand the “effects of … trauma-causing events on persons of all ages” (CACREP, 2009, p. 10). However, even with the notable rates of trauma exposure, the deleterious outcomes faced by survivors and the call for counselor training in this area, counselors report feeling unprepared to work with survivors (Parker & Henfeld, 2012). Over 60% of practicing therapists reported wanting additional support and education in their trauma work (Cook, Dinnen, Rehman, Bufka, & Courtois, 2011). Trauma theorists agree that, with the exception of dissociative identity disorder, no other diagnostic condition in the history of the DSM has created more controversy about boundaries of the condition, symptomatological profle, central assumptions, clinical utility and prevalence than PTSD (Brewin, Lanius, Novac, Schnyder, & The Professional Counselor Volume 4, Issue 3, Pages 257–271 http://tpcjournal.nbcc.org © 2014 NBCC, Inc. and Affiliates doi:10.15241/lkj.4.3.257 Laura K. Jones, NCC, is an Assistant Professor at the University of Northern Colorado. Jenny L. Cureton, NCC, is a doctoral student at the University of Northern Colorado. Correspondence can be addressed to Laura K. Jones, University of Northern Colorado, Department of Applied Psychology and Counselor Education, Box 131, Greeley, CO 80639, laura.jones@unco.edu. Laura K. Jones Jenny L. Cureton Trauma Redefined in the DSM-5: Rationale and Implications for Counseling Practice