Unicoronal synostosis is frequently associated with strabismus. While the literature reports on the underlying bony dysmorphology and associated extraocular muscle dysfunction, the effect of the bony changes of fronto-orbital advancement has unpredictable effects on the strabismus associated with unicoronal synostosis. Previous authors have reported both resolution and new onset of strabismus following fronto-orbital advancement. The purpose of this study is to document the incidence of strabismus in patients with unicoronal synostosis and to assess the effect of fronto-orbital advancement on strabismus. A retrospective review of 20 patients with unicoronal synostosis was performed. The results demonstrated that 90% of our patients were noted to have strabismus preoperatively and this persisted postoperatively. Despite fronto-orbital advancement, strabismus persisted postoperatively. Seven (36.8%) required extraocular muscle surgery. In this series of patients with unicoronal synostosis there was a higher incidence of strabismus than previously reported elsewhere. Correction of the recessed frontal bone with bilateral fronto-orbital advancement does not fully address the orbital bony dysmorphology or correct the extraocular muscle dysfunction associated with unicoronal synostosis.