[en] The relative merit of using calorimetry for standardized measurement of shipper-receiver (S-R) exchanges of plutonium is evaluated. In particular, this evaluation concentrates on the accountability and the diversion detection aspects of the use of calorimetry. Three different modes of use were considered: (1) calorimetry alone, that is, S-R exchanges based on power (watts) measurements; (2) calorimetry plus chemical assay, similar to the present weight plus chemical assay system; and (3) calorimetry plus gamma-ray spectrometry, a totally nondestructive plutonium assay method. The relative merit of each application was judged using the present methods as a base case. Some of the factors considered were random and systematic errors, timeliness, costs (both operating and capital) and reliability