Lots of zebras that can be relevant for basic science and to some extend for clinical science assessment; the focus will be on molecular pathogenesis and diagnostic features of Achondroplasia, Osteogenesis Imperfecta, Dysostoses and Fibrous Dysplasia including the polyostotic variant McCune Albright; A high-yield discussion regarding differential diagnosis off Cafe-au-Lait macules is offered at the end. (Note: Some resources consider Klippel-Feil syndrome also as part of skeletal dysplasias, however we covered it together with disorders of cervical spine in a different episode)