We are more likely than not to be exposed to a clinically defined traumatic event in our lifetime, from experiencing or witnessing serious injury to witnessing death or being subjected to violence, including sexual violence. While the odds of traumatic exposure are high, the likelihood of developing posttraumatic stress disorder (PTSD) is relatively low, as this chapter will show. In addition to PTSD, there are three other trauma and stress-related disorders for adults that are included in the Trauma and Stress-Related Disorders chapter of the DSM-5-TR. These include Acute Stress Disorder, Adjustment Disorder, and the newly added Prolonged Grief Disorder. Both Adjustment Disorder and Prolonged Grief Disorder are stressor-derived and do not necessarily require exposure to clinically defined trauma. The purpose of this chapter is to help clinicians conduct an informed and thorough primary diagnostic evaluation of trauma and stressor-induced disorders. The chapter includes the fundamental elements of each of the four disorders as defined in the DSM-5-TR, including the prevalence of these disorders in the overall population and the sub-groups who are more vulnerable to developing the disorders. In addition, recommendations for formal assessments of each of these disorders will be provided, from structured and semi-structured interviews to screeners. Diversity considerations such as sexual orientation, race, and gender, as well as additional information critical to making a diagnosis as part of clinical interviewing, will also be addressed. Recommendations and “Do’s and Don’ts” for evaluating trauma and stress-related disorders, along with sample evaluative questions about each of the disorders, that clinicians can use in the diagnostic processes are included at the end of the chapter.