A simple, rapid and accurate micro-method for the analysis of mono- and diazide organic compounds is described. It is based on the Curtius rearrangement reaction. Glacial acetic acid is found to be the best decomposition medium. The acyl azide function yields two nitrogen atoms per azide group, but the diazides investigated ultimately give five nitrogen atoms per group on oxidation of their decomposition products, with acidified cerium(IV) sulphate solution. The decomposition time varies from 10 min for monoazides to 20 min for diazides. Accurate results were obtained for a representative series of 18 mono-and diazides.