In January 2000 an EU collaborative project was established to research into methods of disseminating the temperature scale below 1 K. The scale which was formally adopted by the Comite International des Poids et Mesures in October 2000, is the Provisional Low Temperature Scale of 2000 (PLTS-2000). It covers the range of temperature from 1 K down to 0.9 mK, and it is defined by an equation for the melting pressure of ~(3)He. The project will develop and evaluate thermometers, fixed points and instrumentation needed to disseminate the scale to users. Several thermometers are being developed, including Coulomb blockade, noise and magnetic thermometers. A superconducting reference device with 10 - 12 samples is being fabricated to act as a fixed-point device. The full scale, including the ~(3)He transition temperatures, will be realised in several laboratories, and the thermometers and devices will be examined for research, metrological and industrial use. An overview of the project and progress so far will be presented, and plans for the remainder of the project will be outlined.
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