Capillaroscopy is a noninvasive, safe, in vivo study of the capillaries morphology, which can be assessed by using a magnifying system, enabling the early recognition of morphological and functional abnormalities in microcirculation, the most distal area of the circulatory tree. Nailfold capillaroscopy (NC) consists, therefore, in the direct visualization of the distal line of the periungual capillaries. Some conditions that cause changes in the shape and density of the capillaries are systemic sclerosis (SSc), dermatomyositis (DM), mixed connective tissue disease (MCTD), Raynaud’s phenomenon (RP), overlap syndromes, systemic lupus erythematosus (SLE), as well as conditions involving microcirculation such as diabetes mellitus and hypertension (HT).