This chapter takes, as a starting point, the clinically well-known notion that symptoms of chronic orofacial pain are highly variable from patient to patient and that using these symptoms to guide pain treatment is not enough to manage patients successfully. Even when adding etiology as another classifier of the pain, treatment is still only partially effective, and this effect is often attained at the cost of adverse side effects. This chapter reviews recent advances in pain genetics and its application to the orofacial pain field. Using genetic knowledge to guide pain treatment has the potential of accomplishing the goal of eradicating chronic orofacial pain, by offering personalized pain medicine that may prevent the pain from developing and effectively treat it when it has already developed. This chapter will point out that almost everything currently known about the specific genetic underpinnings of orofacial pain has been garnered from a series of recent studies of temporomandibular disorders (TMD), and therefore, much of this chapter is dedicated to describing the genetic findings and plan of operation of these studies.