In the early decades of the twentieth century, ideas about human skin in the United States underwent significant transformation. Initially seen primarily as a functional barrier against the external environment, beginning in the 1920s skin became a mirror of individual internal qualities—a shift driven by new knowledge about hormones, vitamins, psycho-somaticism, and changing ideas about the relationship between self and society. Drawing on both lay and medical sources, this dissertation documents that transformation and also explores how healthy skin became increasingly defined and managed by American systems of industry and commerce. This took place in multiple sites: from the expansion of occupational dermatology confronted by workers plagued by irritants, to academic-industrial partnerships that developed and tested new skin care products in the 1930s and 40s, to consumer research and marketing campaigns that tried to sell soap through individuality and tactility in the 50s and 60s. Within the history of health and medicine, this project addresses a subject that has seen little sustained inquiry to make arguments about the moral expectations of physicians’ logic of irritation and the messy embodied labor of developing consumer products, with the hope of contributing to an ongoing drive to write histories attentive to the influences of the marketplace and consumption. Broadly speaking, by illustrating the multiple meanings of skin in the recent past I aim to loosen the hold of contemporary imperatives toward beauty, perfection, or self-actualization in the body’s surface.