Discovery and development of advanced materials requires understanding and control of the relationship between composition, structure and function. Traditionally, design has relied upon the average structure of the unit cell as determined by Bragg diffraction, but it has become apparent that deviations from this long-range average view of the structure, at length scales both larger and smaller than the unit cell, can have decisive effects. Here, as a key part of a new Leeds-Liverpool EPSRC project, we propose to study three systems: Bi2MgTiO6-BiFeO3-CaTiO3 (BMT-BF-CT) a lead free piezoelectric and room temperature multiferroic, BiFeO3-(K½Bi½)TiO3-PbTiO3 (BF-KBT-PT) high temperature piezoelectrics, and Pb(In½Nb½)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 (PIN-PMN-PT) high strain piezoelectrics which represent best in class properties for single crystal piezoelectric devices.