Homelessness is traumatic, and trauma-informed care is an emerging best practice. Using structured interviews with day shelter clients (N = 152), this study examined trauma among homeless men. The PTSD Checklist (PCL–C) was used to assess for posttraumatic stress disorder (PTSD). Participants’ pattern of PCL–C responses suggested that 23% to 30% screened positive for PTSD. Those with positive PTSD screens had been homeless longer and were more likely to have met time criteria for chronic homelessness. They were significantly more likely to be veterans and to report violent attacks, abuse histories, and mental health problems. Importantly, only 69% of those with positive PTSD screens acknowledged current mental health problems. These individuals were much less likely to report mental health counseling in the prior year.