Objective: To describe a series of patients who used a head tilt to control esotropia. Design: Retrospective noncomparative case series. Participants: Seven children with esotropia that decreased with their compensatory abnormal head tilt. Six of the patients had trisomy 21. The patients had no other identifiable etiology for their head tilt, including no oblique muscle dysfunction, nystagmus that changed with head tilt, or uncorrected refractive error. Intervention: Six patients underwent horizontal extraocular muscle surgery. Preoperative evaluation in 4 patients included assessment of the change in head position with either monocular occlusion or prisms. Main Outcome Measures: Ocular alignment in primary position and improvement in abnormal head tilt after surgery. Results: In the 4 patients who underwent preoperative testing, the abnormal head tilt resolved with either monocular occlusion or prisms. The head tilt and esotropia were eliminated or improved in all patients who underwent strabismus surgery. Conclusions: Abnormal head tilt may be used as a compensatory maneuver to improve purely horizontal strabismus. This finding appears to be associated with trisomy 21. Horizontal extraocular muscle surgery may improve the head tilt in such patients.