The location and quantitative parameters of the motoneurons of three suboccipital muscles are studied by means of retrograde transport of horseradish peroxidase (HRP). Injections of HRP into the M. obliquus capitis superior and into the M. rectus capitis posterior maior result in labeling of somata within the first cervical spinal segment. Injections into the M. obliquus capitis inferior result in labeling within the second cervical spinal segment. All somata are situated within or close to the ventromedial nucleus and show average diameters of about 20-25 microns. Conclusions on the innervation of the suboccipital muscles are drawn.