Bis(hydroxamido)hydroxooxovanadate has been found to undergo favourable condensation reactions with simple peptides such as glycylglycine, glycylglycylglycine, or glycyltyrosine to afford, in each case, three products in the approximate ratio 1:3.5:0.2. The three products had the same ligand stoichiometry and, in the case of glycylglycine, an overall formation constant of 3.3 × 103 M−1for the addition of GlyGly to bis(hydroxamido)vanadate. The51V chemical shift range of the products (close to −850 ppm) overlaps that of the starting complexes and the products may well have a coordination geometry similar to the parent complexes. The chemical shifts observed for these materials are in the range of chemical shifts observed for peroxovanadium complexes. A crystalline monomeric complex with a single glycylglycinato ligand was obtained and its crystal structure determined. The complex is zwitterionic and has a pentagonal bipyramidal coordination at vanadium with the glycine-NH2functionality coordinated in the plane of the two hydroxyalamine ligands and the amido carbonyl oxygen in the apical position. Some comparisons with peroxovanadium complexes are drawn. Crystal structure of V(O)(ONH2)2(GlyGly)•H2O: monoclinic, space groupCc;Z = 4;a = 9.1340(9) Å;b = 16.3355(15) Å;c = 7.1149(6) Å; β(°) = 103.020(7);V = 1034.31 Å3;T = 295 K;RF = 0.21 for 2513 data (I0 ≥ 2.5σ(I0)) and 197 variables.Keywords: vanadate, hydroxylamine,N-methylhydroxylamine, oxobis(hydroxamido)glycylglycinatovanadium(V), peptide complex, glycylglycine,51V NMR, crystal structure.