A liquid development system using a highly concentrated liquid toner has been developed. In this system, the liquid toner is applied as a thin film on the surface of the developing roller, and the roller is brought into contact with an electrostatic medium on which an electrostatic image is developed. The system doesn't require any subtle adjustments of the distance between the developing roller and the medium. Although the system uses highly concentrated liquid toner and contact development, which are usually difficult to handle and can easily cause serious fogging, a clear image can be obtained if certain parameters are optimized. These parameters are the specific peripheral velocity of the developing roller, the electric field between the developing roller and the medium, and the pressure on the contact surface. As a result of this optimization, continuous tone imaging is provided by this system.