There is evidence that Janus kinase (JAK)–signal transducer and activator of transcription (STAT) signaling plays a role in the pathogenesis of sarcoidosis. We treated a patient with cutaneous sarcoidosis with the JAK inhibitor tofacitinib; the patient had not previously had a response to medications and had not received systemic glucocorticoids. This treatment resulted in clinical and histologic remission of her skin disease. Sequencing of RNA and immunohistochemical examination of skin-lesion samples obtained from the patient before and during therapy and immunohistochemical testing of lesion samples obtained from other patients with cutaneous sarcoidosis support a role for JAK-STAT signaling in cutaneous sarcoidosis. (Funded by the Ranjini and Ajay Poddar Resource Fund for Dermatologic Diseases Research and others.)