Chapter 3 starts by covering conditions of the hair, including Alopecias (Loose Anagen Hair, Male Pattern Baldness, and Marie Unna Syndrome), Hirsutism (Gingival Fibromatosis and Hypertrichosis, Hypertrichosis Lanuginosa Congenita, Leprechaunism, and Localized Hypertrichosis), and Hair Shaft Abnormalities (including Monilethrix, Pili Annulati, Pili Torti, Pili Trianguli Et Canaliculi, Trichorrhexis Invaginata, Trichorrhexis Nodosa, Woolly Hair, Menkes Disease, Trichodentoosseous Syndrome, Trichorhinophalangeal Syndrome, and Trichothiodystrophy). It then covers conditions of the nails, including Congenital Malalignment of the Great Toenails, Familial Dystrophic Shedding of the Nails, Leukonychia, Twenty-Nail Dystrophy, Nail-Patella Syndrome, Onychotrichodysplasia and Neutropenia, and Pachyonychia Congenita). Conditions of the Sweat Glands (Hidradenitis Suppurativa, Hyperhidrosis, and Multiple Syringomas), Sebaceous Glands (Eruptive Vellus Hair Cysts, Familial Dyskeratotic Comedones, Oral-Facial-Digital Syndrome Type I, and Steatocystoma Multiplex), and Ectodermal Dysplasia Syndromes (AEC Syndrome, Clouston Syndrome, EEC Syndrome, Focal Facial Ectodermal Dysplasia, GAPO Syndrome, Hypohidrotic Ectodermal Dysplasia, and Tooth and Nail Syndrome) are also covered. Each condition is discussed in detail, including dermatologic features, associated anomalies, histopathology, basic defect, treatment, mode of inheritance, prenatal diagnosis, and differential diagnosis.