The High Density Lidar - Grand Est program provides for the implementation of digital 3D description equipment with an accuracy never achieved on the scale of the Grand Est region. To this end, it uses state-of-the-art technology that has proved its worth: high-density LiDAR (target: 10 points per square metre on average). The programme meets the needs of observation and spatial analysis in many areas of public action (risk prevention, observation of forest resources, land use planning, energy transition, etc.) and is a lever for the development of future value-added services. By making this rich, multi-purpose and interoperable data with existing geographical repositories available to all, the High Density LiDAR - Grand Est program is not only a generator of savings, but also a strong lever for the development of services in many areas, probably far from being all identified to date, whether for the benefit of public policies, as a driver for the development of SMEs or as a breeding ground for scientific research.