<b><i>Introduction:</i></b> Individuals exposed to interpersonal violence (IPV) commonly develop posttraumatic stress disorder (PTSD) with co-occurring depression and insomnia. Standard PTSD interventions such as cognitive processing therapy (CPT) do not typically lead to remission or improved insomnia. Cognitive behavioral therapy for insomnia (CBTi) improves insomnia in individuals with PTSD, but PTSD severity remains elevated. <b><i>Objective:</i></b> To determine whether sequential treatment of insomnia and PTSD is superior to treatment of only PTSD. <b><i>Methods:</i></b> In a 20-week trial, 110 participants exposed to IPV who had PTSD, depression and insomnia were randomized to CBTi followed by CPT or to attention control followed by CPT. Primary outcomes following CBTi (or control) were the 6-week change in score on the Insomnia Severity Index (ISI), the Clinician-Administered PTSD Scale (CAPS), and the Hamilton Rating Scale for Depression (HAM-D). Primary outcomes following CPT were the 20-week change in scores. <b><i>Results:</i></b> At 6 weeks, the CBTi condition had greater reductions in ISI, HAM-D, and CAPS scores than the attention control condition. At 20 weeks, participants in the CBTi+CPT condition had greater reductions in ISI, HAM-D, and CAPS scores compared to control+CPT. Effects were larger for insomnia and for depression than for PTSD. Similar patterns were observed with respect to clinical response and remission. A tipping point sensitivity analyses supported the plausibility of the findings. <b><i>Conclusions:</i></b> The sequential delivery of CBTi and CPT had plausible, significant effects on insomnia, depression, and PTSD compared to CPT alone. The effects for PTSD symptoms were moderate and clinically meaningful.