The development of InP materials and devices for oscillators and amplifiers has led to a number of products which are now being used in prototype millimeter-wave systems. The InP Gunn device is being developed specifically for low noise amplifiers from 26 GHz through 100 GHz and for medium power low noise oscillators from 40 GHz through 140 GHz. The use of the InP Gunn diode as a low noise amplifier has led to new developments which use the InP Gunn diode in medium power amplifier applications. The InP IMPATT also appears attractive as a millimeter-wave power device, especially in the 30 GHz to 100 GHz region, and it is now being developed at Ka-band frequencies. This paper summarizes the state of the art of the InP Gunn device, both for low noise and medium power amplification and for oscillators at 60 and 94 GHz. Also, results on the InP IMPATT development are presented.