Recent studies suggest that hydrophilic interactions play an important role , in controlling self-assembly in biological processes. To explore the effect of temperature on this interaction, we extend our previous work on the glutamine-water system at 24 degrees C (at a mole ratio of 1 glutamine to 269 water molecules) and present additional neutron diffraction data, at the same concentration, at 37 and 60 degrees C, using hydrogen/deuterium substitution on the water and glutamine, coupled with further extensive empirical potential structure refinement computer simulations. Taking all the possible hydrophilic couplings between glutamine molecules into account, we find that nearly one-fifth of the glutamines in solution are linked by hydrogen bonds at any one time. This number contrasts strongly with the similar to 3-4% fraction found in the same simulation with random packing and no hydrogen bonds. Within the uncertainties imposed by dilute solution statistics, we find no temperature dependence in these values. The clusters are highly transitory, forming and disappearing rapidly as the simulations proceed. Hydrophobic association of the alkyl groups on glutamine without concomitant hydrophilic association of the charged head and is only weakly observed.