Weak localization of light or coherent backscattering (CBS) of light is a phenomena in which partial waves traversing momentum-reversed (time-reversed) scattering paths interfere constructively in the backscattering direction leading to an enhancement of scattered light intensity. The enhancement of intensity is proportional to a reduction of light transported in the scattering medium. Thus the CBS signal is a measure of localization of light in the scattering medium. We are building an apparatus to observe weak localization of photons in a high density sample of ultra-cold atoms. First we slow the atoms from room temperature (300 m/s) to less than 10 cm/s in a magneto-optical trap (MOT) where the atom number density is 10 11 atoms/cm 3 . In order to increase the atomic density the atoms in the MOT are transferred to a far detuned microscopic dipole trap created by a laser focused to a waist of approximately 5m. We have successfully loaded the MOT and are now in the process of loading the high density microscopic dipole trap. Once this is achieved we will look at the CBS signal as a function of the atom number density and the scattering cross section. The goal of the project is to reach the Joffe-Regel region where mean free path length is about the wavelength of the scattering radiation.