We present an automated method for nonrigid registration of the optic nerve head (ONH) surfaces extracted from 3-D optical coherence tomography images to give a one-to-one correspondence between two ONH surfaces. This allows development of population-average ONH surfaces, pooling of morphometric data measured on ONH surfaces from multiple subjects into a single chosen template surface, and statistical analysis (cross sectional, or longitudinal, or both) in a common coordinate system. An application of this coordinate system to construct an average ONH shape across an illustrative dataset is demonstrated, and the impact of template selection is assessed.