The Atmospheric Lidar (ATLID) is the backscatter lidar instrument developed for ESA, under the prime contractorship of MATRA MARCONI SPACE France. This kind of lidar has been selected for flight on an ESA Earth Explorer satellite, and will be based on ATLID concept and technologies. It is part of a multi-payload mission, named Earth Radiation, dedicated to the Earth radiative transfer study for climatology. The lidar will provide information on the atmosphere, such as cloud cover, top height of all cloud types and planetary boundary layer, thin cloud extent, optical depth and polarization. The instrument features a pulsed diode-pumped Nd-YAG laser (1.06 micrometers wavelength) together with a one-axis scanning 60 cm lightweight telescope. A technology pre-development program has been performed in order to raise the maturity of the instrument design. Elegant breadboard models have been realised and submitted to environmental tests. The laser transmitter, the laser thermal control subsystem (capillary-pumped two-phase loop), the diode laser power supply, the avalanche photodiode detection chain, the narrow-band filter, the scan mechanism, and the telescope lightweight primary mirror (C-SiC) have been breadboarded in the frame of the programme. The instrument design and performance have also been consolidated with regards to the successful hardware results.