The dense cores of interstellar molecular clouds are sufficiently shielded from dissociating ultraviolet radiation to allow the formation of complex molecu les. In particular, a number of organic molecules have been identified by their radio and millimeter wavelength rotational spectra. While relatively complex species, like methyl ethyl ether (CH3OC2H5), have been discovered, unequivocal evidence for bona fide biomolecules, such as the simple amino acid glycine, remains elusive despite extended searches. This talk gives a brief summary of the current state of this field.