This investigation aimed to examine how specific client characteristics of individuals with chronic, complex trauma are associated with the type coping strategies they employ and the quality of the therapeutic alliance. Fifty-nine adult participants with diagnostic levels of posttraumatic stress disorder (PTSD) and who attended therapy for complex trauma in Northern Ireland were obtained via opportunity sampling. Participants completed self-report measures of client attachment style, alexithymia, coping strategies, and the therapeutic alliance. Preoccupied attachment factors such as “Need for Approval” and “Preoccupation with Relationships” were related to use of maladaptive coping strategies. In contrast, the adaptive coping strategies of “Acceptance” and “Instrumental Support” were significant predictors of a positive therapeutic alliance, whereas established psychological and traumatogenic factors (e.g., attachment, number of traumatic events) did not significantly predict the therapeutic alliance. The findings have implications for understanding the relationship between client characteristics and the therapeutic alliance within complex trauma populations, as well as developing protocols to assist this process.