Synchrotron infrared measurements of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) have been performed in the far-IR and mid-IR spectral regions up to similar to 30 and similar to 40 GPa, respectively. For the far-IR experiment, no pressurizing medium was used, whereas KBr was utilized as a pressurizing medium for the mid-IR experiment. For both experiments, pressure was cycled and IR spectra were recorded at various pressures to ascertain sample survival. In the high frequency region (similar to 3000 cm(-1)) of the mid-IR spectra, the peak frequencies of the NH2 symmetric and antisymmetric vibrational modes steadily decrease with increasing pressure, indicating strengthening of intermolecular hydrogen bonding with pressure. In both experiments, no apparent phase transition was observed to the highest pressures studied.