A new spectroscopic method of monitoring the base-catalyzed decomposition of nitramide, NH2NO2, has permitted detailed study of this reaction in basic solutions where accurate data could not be obtained previously, and that has led to the discovery of a second reaction pathway in addition to the traditional route. Newly determined catalytic coefficients for the traditional pathway plus some literature values describe an accurately linear Bronsted relation with beta = 0.79 +/- 0.01 which extends from -log (q(K)a/p) = 1 to 8 and to which oxygen and nitrogen bases of different charge type (-2, -1, 0, + 1) adhere well. Above -log q(K)a/p) = 8, this Bronsted relation begins to curve downward and disperse into different correlations for nitrogen and oxygen bases. Corresponding behavior is shown by kinetic isotope effects on the decomposition reaction: these are constant at k(H)/k(p) = 2-3 and independent of base type up to -log (q(K)a/p) = 8, but beyond this point, they rise and begin to define maxima which again are different for oxygen and nitrogen bases. This behavior is interpreted in terms of a reaction mechanism in which the proton transfer and heavy atom bonding changes required to convert nitramide into its decomposition products, N20 and H20, are not concerted but rather occur in separate reaction steps.