Cylindrical plastic scintillators were investigated for efficiency in detecting neutron-induced prompt gamma rays. Scintillator performance was compared on the basis of half-resolution and peak-to- trough ratios for gamma spectra obtained from co-60 (1.17 and 1.33 Mev), th-228 (2.62 Mev), and pube (4.43 Mev). Various sizes of pilot chemical scintillators (types b, f, m, and y) were tested. The best half-resolution, 7.7 percent for pube, was achieved with a 5- by 5-inch pilot y-scintillator and dual photomultipliers. Comparison with sodium iodide (nai) scintillators and the use of plastic scintillators for on-stream analysis of sulfur in coal is discussed. Plastics were found to be unsuitable for on-stream analysis of materials having complex prompt gamma ray spectra; however, they could conceivably be used for those yielding simpler spectra.