Ticks (Acarina: Arachnida: Arthropoda) are obligate, nonpermanent ectoparasites of terrestrial vertebrates. In arthropods, ticks are second only to mosquitoes in the number of pathogens they transmit to people, domestic pets, livestock, and wild animals. Ticks are vectors to a variety of human diseases, including Rocky Mountain spotted fever, Lyme disease, Colorado tick fever, tickborne encephalitis, babesiosis, tularemia, and tick-borne relapsing fever. In addition, other maladies due to tick bites, such as tick paralysis, tick toxicosis, and anaphylaxis, are common. Each year, worldwide public health and agricultural industry costs due to tick-transmitted diseases are estimated to be in the range of several billion U.S. dollars. To date, the control of ticks has relied heavily on chemical pesticides (acaricides). The excessive use of pesticides in tick control has resulted in environmental contamination, food safety concerns, and pesticide resistance. Consequently, use molecular technology to develope anti-tick vaccines is an essential alternative strategy in tick and tick-borne disease control. Recent studies and the status of anti-tick vaccine development are reviewed in this chapter.