Abstract: A novel dimming assembly for controlling light intensity of a gas discharge lamp, including:dimming controller having an input terminal connectable to one pole of an alternating current source and having an output terminal connectable to the line leading to one of the two filament electrodes of the lamp, the dimming controller being adapted to provide an attenuated and conditioned power at its output terminal;the dimming controller being adapted upon feeding the input terminal with the current, to operate in full power mode for a time period t.sub.1, during which the link between the two terminals is in full conductance bringing about full light intensity of the discharge lamp, and being further adapted after t.sub.1 to enter into a dimming mode, during which the link between the two terminals is in partial conductance bringing about attenuated intensity of the discharge lamp; the said time t.sub.1 is sufficient to facilitate effective dimming in the dimming mode.