A treatment for subcutaneous fat and/or cellulite includes a system (30) to non-invasively deliver a beam of radiation to a target region of skin, comprising: an optical energy source (32) and a handpiece (36) the handpiece (36) includes an optical system to direct the beam of radiation to the target region of skin, the handpiece is further configured to be positioned: a) in contact with a skin surface, b) adjacent a skin surface, c) proximate a skin surface, spaced from a skin surface, or a combination of aforementioned； characterized in that the optical energy source (32) provides a beam of radiation within a range of wavelengths that can be transmitted to fatty tissue and absorbed by the fatty tissue in a target region of skin； and wherein the wavelength is one of a group of wavelengths consisting of the wavelength about 1,208 nm, 1,270 nm, 1,310 nm, 1,450 nm, 1,550 nm, 1,720 nm.
