The dielectrophoretic response of different solids is investigated in liquid media of various permittivities and resistivities. The solids investigated had a wide range of both relative permittivity (3.8 to 350) and resistivity (10^-4 to 10¹⁶ Omega m). The use of dioxane and water solutions provided liquid media of controllable relative permittivity in the range 2.2 to 80. The response, which is found to be frequency dependent, is determined for various combinations of insulating and conducting materials at three frequencies: 10² Hz, 10⁴ Hz and 2.55 MHz. The results show that the resistivities of the materials exercise a control over the response comparable to that of their relative permittivities. The correlation of the observed response with that predicted using a theory developed for non-insulating materials is discussed.