Scleroderma (SSc) is an autoimmune disease characterized by fibrosis (or collagen deposition) of the skin and internal organs. The extent of skin fibrosis is an important predictor of internal organ complications and increased mortality. Currently imprecise and subjective methods that varies amongst different doctors for the same patient are available to quantify skin fibrosis in patients, by pinching their skin and assessing how thick it is; this is the method used to determine the modified Rodnan skin score (mRSS). Skin thickness and the amount of fibrosis can change over time due to disease progression or in response to therapy. In this research, longitudinal measurements will be taken to determine if spatial frequency domain imaging (SFDI) can detect changes in skin thickness that occur over time in response to therapy or from disease progression in scleroderma patients. This study will compare SFDI with other clinical outcome assessments of skin thickness and fibrosis in scleroderma patients including mRSS, skin biopsy histology, scleroderma skin patient reported outcome (SSPRO), ultrasound, and durometry (durometer measures skin hardness). SFDI information will also be compared with capillaroscopy (allows for non-invasive imaging of the nailfold capillaries) if available from the electronic medical record. If SFDI correlates well with other clinical outcome assessments, it may be used in the future as a rapid, non-invasive tool for monitoring disease activity in scleroderma patients.