The diagnosis of restless legs syndrome is usually relatively straight forward in adults if all of its symptoms are present. However, because the unusual leg sensations can be mimicked by other diseases (for example, nerve, nerve root or spinal cord damage), they can sometimes be difficult to recognize as RLS per se. More rarely, symptoms can predominate in other body locations such as the neck, arms, trunk, or abdomen. Together, these unusual presentations can lead to lengthy, expensive, and unnecessary testing. Features that support a diagnosis are: 1) a history of RLS in a first degree relative; 2) a previous favorable response to medications that enhance brain dopamine signaling (or worsening with medications that interfere with this signaling); and 3) the presence of PLMs. Therefore, in cases in which the diagnosis might be less clear, small, light-weight accelerometers can be worn on one’s ankle to detect PLMs at home. As PLMs are known to vary on a night-to-night basis rather substantially, devices are usually worn for 3-5 nights to gain an adequate picture. Less commonly, a dedicated sleep test (polysomnography) is performed overnite in a sleep laboratory.