Case: The authors report a child born with a constellation of findings including Chiari I malformation, Pierre Robin syndrome, and caudal regression syndrome. In addition, this child was found to have a fatty-infiltrated filum terminale and a low conus medullaris. Discussion and conclusion: In isolation, the Chiari I malformation has been reported in patients with caudal regression and Pierre Robin syndrome. Speculation has been given to the possibility of a common insult to early mesodermal development and each of these pathological entities. To our knowledge, this is the first report of a single patient that possessed all three entities (i.e., Chiari I malformation, Pierre Robin syndrome, and caudal regression syndrome). Further case reports as this may shed light on the dysembryology that results in each of these diagnoses. © Springer-Verlag 2006.