This chapter describes temperature and thermal history sensors based on microparticle or nanoparticle luminescence. A sensor that could work within these limitations is a block of material with some nonvolatile, temperature-dependent property. A luminescent material is one that emits light in response to some external stimulus such as heat or optical pumping. The use of mineral or ceramic luminescence to determine temperature has been utilized previously in the space sciences and archaeology but not extensively because of complications in assessing initial trap populations, among other issues. The thermoluminescence (TL) of these particles is an indication of trap population and thus gives one insight into the thermal history of the particle. Trap luminescence has also been used to obtain information about the firing temperatures of pottery. The microheaters can often eschew the complex control schemes needed to deal with response delay and ringing in conventional hotplates.