A method of switching an electrically actuated variable transmission layer is disclosed. The layer is between a first electrode and a second electrode, and when a sufficiently high frequency alternating electric field is applied between the first and second electrodes, a selective region of the layer in between the first and second electrodes is switched. Apparatus for use as a glazing pane having a sheet of glazing material and an electrically actuated variable transmission layer facing the sheet of glazing material is also disclosed. The layer is sandwiched between a first electrode and a second electrode. There is an electric field generator in electrical communication with the electrodes and being configured to produce an alternating electric field of sufficient strength and of a sufficiently high frequency to switch a selected region of the layer in between the first and second electrodes.