HRPD data will be collected in situ at low and high temperatures from perovskites belonging to the Sr(ZrxTi1-x)O3 solid solution which have recently been characterised for their anomalous elastic and anelastic properties by Resonant Ultrasound Spectroscopy. Four samples are representative of different patterns of elastic softening: x = 0.8 (500-1275 K), 0.55 (300-1100 K), 0.225 (4-800 K), 0.025 (4-300 K). Lattice parameters, octahedral tilt angles and space group information will be extracted by Rietveld refinement. These, in turn, will be analysed in terms of symmetry breaking strain/order parameter relationships predicted from a full Landau expansion for combined M- and R-point tilting transitions. The crystallographic information thus obtained will be invaluable in allowing the elastic behaviour to be interpreted in terms of specific phase transitions and elastic softening mechanisms.