Imprinting oxides Dislocations can be problematic for the properties of functional oxides and are often avoided as a result. Höfling et al. found that introducing a network of dislocations to barium titanate actually enhanced the dielectric and piezoelectric properties. The authors introduced the dislocation network with uniaxial compression, which forced the material to have a domain structure that enhanced the piezoelectric coefficient by a factor of 19. This strategy should be a useful tool for optimizing properties of other functional oxides. Science , abe3810, this issue p. 961