Multiply-charged anions derived from electrospray have been subjected to reactions with singly-charged cations of argon, krypton, and xenon in a quadrupole ion trap. The doubly-charged anion formed from a sulfonated azo dye and the highest negative charge states formed from the polyadenylates 5’-d(AAA)-3’, 5’-d(AAAA)-3’, and 5’-d(AAAAA)-3’ sen ed as the anionic reactants. In each case, extensive fragmentation of the anionic product, which presumably is a radical anion, was observed. Comparison of the observed decomposition products arising from ion/ion reactions with product anions formed via collisional activation of the even-electron species of the same charge state, as formed directly by electrospray, shows significant differences. While both the even-electron and odd-electron species hold some fragmentation pathways in common, the odd-electron species show one or more additional decomposition channels. Furthermore, in the case of the polyadenylate anions, the ion/ion reactions showed more nearly equal contributions from the major dissociation channels that yield sequence information than did collisional activation of the corresponding even-electron anions.