It is here shown how the tag design procedure can be modified to take the presence of a specific sensor into account. As an example, a very simple mechanical motion sensor is considered, and a fully integrated wearable sensor RFID tag is designed, fabricated and hence experimentally evaluated. The detection of the motion, in particular, is of great interest in medical application, to assist the diagnosis of some neurological diseases, involving compulsory arms movements [20], in domestic healthcare, to track the behavior of elderly, but also in logistic and security to control limited-access areas.