"This proposal brings together a group of universities, research organisations and high-tech companies from different disciplines (meteorology, geosciences, physics, electrical engineering, mathematics) with the aim to foster training and further development in the area of remote sensing of the atmosphere. The last years have brought a rapid development in instrumental techniques, i.e. lidar, radar, radiometry, that have great potential to monitor atmospheric composition and dynamics in unprecedented detail. Such instrumentation is urgently needed to address important topics related to climate change, numerical weather forecasting, and atmospheric pollution. Most prominently aerosol-cloud interaction as the single largest uncertainty in current climate projections requires the exploitation of emerging observational techniques to improve the parameterisation of aerosol and cloud processes in atmospheric models. Because today’s curricula do not reflect these issues, ITARS (Initial Training for Atmospheric Remote Sensing) aims• to impart an in-depth understanding of instrumentation and algorithms needed to retrieve geophysical quantities and atmospheric applications,• to foster the synergy of different sensors by bringing together experts from the individual techniques,• to develop and implement pan-European courses on atmospheric remote sensing by exploiting new web-based techniques, and• to close the gap between the specialized development of single instruments and atmospheric applications by training a new generation of scientists in academia and the private sector."