The microwave spectra of ethanol (C2H5OH) and propionitrile (ethyl cyanide, C2H5CN) are critically reviewed and supplemented with spectral frequency calculations which include rotational and centrifugal distortion terms in the molecular Hamiltonian. The primary objective of this review is to provide the microwave transition frequencies applicable to molecular radio astronomy for the ground vibrational state of the most abundant isotopic forms, namely,12C2H516OH and12C2H512C14N. Since the internal rotation and hyperfine splittings for these species have not been resolved in most of the reported laboratory studies and also not detected in the molecular clouds observed by radio astronomers, these splittings have been ignored in the present calculations. All measured rotational transitions are included, however, the predicted transition frequencies were limited toJ= 25 for ethanol andJ= 30 for propionitrile over the range of 1 GHz to 300 GHz. A complete summary of the laboratory studies of both species is included for all isotopic forms with references to all prior studies.