Inhibition of the glycolytic enzyme phosphoglycerate kinase (PGK) in erythrocyte cells could provide a method of treatment for cardiovascular and respiratory disorders. The product of the reaction catalysed by PGK, 1,3-diphosphoglycerate, is converted by another enzyme in erythrocytes to 2,3-diphosphoglycerate, which is an allosteric effector of haemoglobin. For this reason, a series of fluoro-phosphonate inhibitors have been tested for their potency in detailed inhibition kinetic experiments with yeast PGK. The results were analysed by Lineweaver-Burk and Dixon plots and Ki values obtained. Two fluorophosphonates were found to be inhibitory and both have an electron rich mid-chain functionality, which is thought to provide electrons for hydrogen bonding to residues in the triose binding site of the enzyme. It is postulated that either the fluorine or mid-chain moieties of the analogues are binding to Asp23 and Asn25 residues in the so called 'basic patch' area of the triose site. These residues are shown to bind to the D-hydroxyl moiety on the C2 of the true substrate, 3-phosphoglycerate, in the high-resolution crystal structure of pig muscle PGK co-crystallized with 3-phosphoglycerate.