High-resolution VLA radio mapping at 1.46, 4.84, and 15.0 GHz is presented together with NIR J,H,K,L, and M mapping and photometry of a broad range of type I postmain-sequence nebulae. Many of these sources have extremely compact infrared and radio cores ranging from 0.1 to 0.01 pc in size; in some cases they contain up to 96 percent of the total radio flux. A detailed investigation of the IRAS photometry for type I nebulae was undertaken; a typical interior grain temperature is estimated to be 200 K while outer shell temperatures are estimated to be less than 50 K.