Electrophotographic printing apparatus and method of printing using electrophotographic printing apparatus, the apparatus comprising an image-forming member having a surface on which a latent electrostatic image can be formed and developed for transfer of the developed image to a substrate via an intermediate transfer member. The apparatus comprises a voltage supply for generating electric potential between the surface of the intermediate transfer member and the image-forming member such that the developed image formed on the surface of the image-forming member is transferred to the intermediate transfer member. A controller of the apparatus controls the voltage supply to adjust the electrical potential to affect the transfer of ink to the intermediate transfer member from the image-forming member. In this way, the apparatus can adjust for changes in the electrical properties of the intermediate transfer member.