The atlas aims to provide students and researchers of birth defects in academia, drugs and chemical industry, veterinary fields, aquaria and governmental authorities for environment with a set of images of both rare and common observations in fetuses and neonates from common laboratory, domestic and wild animals and birds. The terminology adopted in this atlas is based upon the glossary published by members of the International Federation of Teratology Societies (IFTS) Committee on Harmonization of Terminology in Developmental Toxicology.