In an attempt to delve into the chemistry of boron, whose role in biology still remains unclear, yet its presence and influence is undisputed, research was launched into the structural speciation of B III with physiological binders. The latter molecules involve hydroxycarboxylic glycolic, 2-hydroxy-isobutyric, and citric acids. Their pH-specific reactivity is systematically investigated synthetically in binary and ternary systems of B III , leading to well-defined crystalline materials, [