A phototherapy device includes a light source; a light emanation block; and a heat exchanger for the dissipation of heat from one or more heat loads associated with the device. Heat may be transferred via the heat exchanger from the light source independently of the dissipation of heat from one or more of the other device heat loads. Substantially thermally isolated heat transfer regions may be provided, and such regions may be maintained at different operating temperatures, to control the transfer of heat in conjunction with a phototherapy method and to promote efficient and enhanced device operation and performance.