Optical coherence tomography (OCT), a fairly new non-invasive optical real-time imaging modality, is an emergent in vivo technique, based on the interference (Michelson interferometry) of infrared radiation and living tissues, that allows high-resolution, 2- or 3-dimensional, cross-sectional visualisation of microstructural morphology of tissues. OCT provides depth-resolved images of tissues with resolution up to a few micrometers and depth up to several millimetres depending on tissue type. The investigations using OCT to assess skin structure in clinical settings started in the past decade and consequently proved that this imaging method is useful in visualizing subsurface structures of normal skin, including the epidermis, dermoepidermal junction, dermis, hair follicles, blood vessels and sweat ducts. An increasing number of papers brought evidence of the utility and the precision of OCT technology, in its different technical variants, in diagnosing and monitoring skin disorders, including malignancies and inflammatory conditions, respectively. The present comprehensive review describes and illustrates technical aspects and clinical applications of OCT methods in dermatology.