The global representation of aerosol, clouds, and their impact on the energy budget remains a major source of uncertainties in global models for climate predictions, but also strong weather events in numerical weather prediction. Earth Cloud, Aerosol and Radiation Explorer (EarthCARE) mission, the sixth Earth Explorer Mission of the European Space Agency (ESA) Living Planet Programme, shall improve the understanding by three dimensional observations of global profiles of cloud, aerosol, precipitation and associated radiative properties. A major contribution will be provided by the ATmospheric LIDAR (Light Detection and Ranging), ATLID, being developed and tested by Airbus Defence and Space S.A.S in Toulouse. ATLID is a High Spectral Resolution-Polarization LIDAR and will provide vertical profiles of optically thin cloud and aerosol layers, the aerosol type, as well as the altitude of cloud boundaries. After the development, qualification and delivery of all units, ATLID integration has finally been completed and the self-standing instrument was successfully tested to demonstrate its performance under ambient and space environment conditions, in Toulouse and CSL/Liège respectively. All preliminary test results obtained up to now are very promising and indicate ATLID's capability and compliance to all performance goals and specifications. The instrument has been now delivered, to Airbus Defence and Space GmbH Immenstaad, and integrated into the EarthCARE platform. Results of ATLID ambient test campaign, EMC, mechanical test campaign, and thermal balance test campaign, along with final performance and calibration test results shall be presented in this paper.