Recent developments and new applications of the NRHB equation-of-state model are reported. The essentials of the non-randomness and hydrogen-bonding formalism are summarized along with an extension to solutions of electrolytes. The model is critically compared with other widely used equation-of-state models in terms of their capacity for correlation and prediction of phase equilibria of representative classes of systems. The applications include aqueous polymer and copolymer solutions, hydrogels and gel collapse, electrolytes in mixed solvents, sorption into glassy polymers, design of nanofoams, and interfacial profiles. Limitations, simplifications, and future extensions are discussed.