A child with Goldenhar's syndrome presented at about one week of age with stereotyped, repetitive paroxysmal episodes of hemifacial contraction, suggestive of partial seizures or hemifacial spasm. Later in life he also developed independent, permanent abnormal eye and chin movements identical in rhythm to those seen in myorhythmias, suggesting involvement of the dentato-olivary pathway. MRI demonstrated a hamartomatous lesion at the level of the pontomedullary junction. We speculate that the nature of the lesion could be responsible for the partial seizures mimicking hemifacial spasm and that because of its location, this same lesion could also be implicated in the genesis of myorhythmias. The presence of a hamartomatous lesion in a region affected by the abnormal development of the first and second branchial arches is not fortuitous.