Posttraumatic headache (PTH) is a common debilitating condition arising from head injury and is highly prevalent among military service members and veterans with traumatic brain injury (TBI). Diagnosis and treatment for PTH is still evolving, and surprisingly little is known about the putative mechanisms that drive these headaches. This manuscript describes the design of a randomized clinical trial of two nonpharmacological (i.e., behavioral) interventions for posttraumatic headache. Design of this trial required careful consideration of PTH diagnosis and inclusion criteria, which was challenging due to the lack of standard clinical characteristics in PTH unique from other types of headaches. The treatments under study differed in clinical focus and dose (i.e., number of treatment sessions), but the trial was designed to balance the treatments as well as possible. Finally, while the primary endpoints for pain research can vary from assessments of pain intensity to objective and subjective functional measures, this trial of PTH interventions chose carefully to establish clinically relevant endpoints and to maximize the opportunity to detect significant differences between groups with two primary outcomes. All these issues are discussed in this manuscript.