A presence or an absence of an occupant is detected, and an occupancy sensor signal is generated representative of an active state in which the presence of the occupant is detected, and an inactive state in which the absence of the occupant is detected. An ambient light sensor detects the ambient light level and generates an ambient light sensor signal representative of the ambient light level. Dimmable illumination is generated at a first dimming level, based on the ambient light level, corresponding to the active state and a second dimming level corresponding to the inactive state. A transition delay time between an onset of the inactive state and a transition between the first dimming level and the second dimming level may be controlled. The first dimming level, the second dimming level, and/or the transition delay time may be variably set or controlled locally or via a remote device.