Protein profiling offers an effective approach to characterizing the departure from normal of epidermis in disease states. The present investigation tested the hypothesis that the differentiation of epidermal corneocytes is perturbed in the forehead of subjects exhibiting frontal fibrosing alopecia. To this end, samples were collected by tape stripping from subjects diagnosed with this condition and compared to those from asymptomatic control subjects and from those exhibiting androgenetic alopecia. Unlike the latter, which exhibited only 3 proteins significantly different from controls, forehead samples from frontal fibrosing alopecia subjects displayed 72 proteins significantly different from controls, nearly two-thirds having lower expression. Comparison to corresponding profiles in scalp samples from frontal fibrosing alopecia and androgenetic alopecia suggested the perturbation of epidermal differentiation in the former was even greater in the scalp.