Halpern's distinguished contributions are in several areas. Elegant and sensitive procedures for detection of chiral amino acids and their use for detection of extra terrestrial life, (The Pasteur Probe). The application of combined mass spectrometry and enzymic methods to the sequencing of proteins microanalytically. This will become one of the routine methods for sequencing proteins. Finally GC-MS and stable isotope techniques have been used to diagnose and study metabolic disorders and genetic defects (in collaboration with Professor Danks). These are pioneering studies with an impact on medicine, biochemistry, chemistry and geochemistry, and Halpern is acknowledged by all four areas as an authority in his field.