This chapter discusses the two general parts of the skin and their origins. These are: epidermis and dermis. The epidermis consists of several strata. Specialized parts of the skin—hair, glands, and nails—arise from interactions between the epidermis and dermis. Some of the epidermis's cells originate in the neural crest. The dermis of the skin is primarily derived from the mesoderm. The dermis of the dorsal part of the body develops from the dermatomal portions of somites, and the ventral dermis develops from somatic mesoderm. The chapter presents the appendages of the skin and describes the development of hair and glands. The role of epithelial—mesenchymal interactions in development is exemplified by the development of the skin and its derivatives. The development of organs, which consist of an epithelium and mesenchyme, are clearly among the most important aspects of development. The chapter explores the developmental interaction between the epidermis and dermis.