Ultraviolet (UV) radiation is the carcinogenic factor in sunlight. Damage to skin cells from repeated UV exposure can lead to the development of skin cancer. Apart from avoidance of the sun, the most frequently used form of UV protection has been the application of sunscreens. The use of textiles as a means of sun protection has been underrated in previous educational campaigns, even though suitable clothing offers usually simple and effective broadband protection against the sun. Apart from skin cancer formation, exacerbation of photosensitive disorders and premature skin aging could be prevented by suitable UV-protective clothing. Nevertheless, several studies have recently shown that, contrary to popular opinion, some textiles provide only limited UV protection. It has been found that one-third of commercial summer clothing items provide a UV protection factor (UPF) less than 15. Given the increasing interest in sun protection, recreationally and occupationally, test methods and a rating scheme for clothing were needed that would ensure sufficient UV protection. Various textile parameters have an influence on the UPF of a finished garment. Important parameters are the fabric porosity, type, color, weight and thickness. The application of UV absorbers into the yarns significantly improves the UPF of a garment. Under the conditions of wear and use several factors can alter the UV-protective properties of a textile, e.g., stretch, wetness and laundering. The use of UV-blocking cloths can provide excellent protection against the hazards of sunlight; this is especially true for garments manufactured as UV-protective clothing. However, further educational efforts are necessary to change people's sun behavior and raise awareness for the use of adequate sun-protective clothing.