Ticks are very widespread cosmopolitan arachnid arthropods, haematophagous parasites to mammals, birds and reptiles. Besides their usual hosts, which represent the real reservoir of these parasites, they can adapt themselves to alternative hosts, including man. Ticks cause cutaneous, lesions (granulomas and necrosis) at the site of the bite, and often provoke allergic reactions especially in previously sensitized persons. They are also carriers of many bacterial and viral infections, some of which have not yet been studied fully (e.g., arboviruses). The most common dermatoses due to tick bites are described briefly below. The most common species of ticks in Europe are Ixodes ricinus (sheep tick) and Rhipicephalus sanguineus (dock tick).