"ASTRODEEP is a co-ordinated and comprehensive program of i) algorithm/software development and testing; ii) data reduction/release, and iii) scientific data validation/analysis aimed at making Europe the world leader in the exploitation of the deepest multi-frequency data. We will focus on 5 key extra-galactic survey fields, the target of public observing programs motivated by the desire to understand the formation and evolution of galaxies and super-massive black holes from the very earliest times, and to answer fundamental questions in cosmology such as how and when the universe was re-ionized. They include data from space, notably from HST, XMM, Herschel and Spitzer, and from several optical and far-IR ground based facilities. The main technical problems we seek to overcome relate to the varying depth and, most importantly, widely-varying angular resolution of the data delivered by observatories working over a wide range of frequencies. The focus of this project is on bringing together the expertise of our team to develop, refine and combine advanced algorithms for data analysis, test and properly validate their effectiveness on the deepest multi-frequency data, and apply them to produce uniquely powerful homogenized data products (for all 5 deep survey fields).We will deliver the final data in the form of a) final stacked images, b) multi-wavelength catalogues, spectral energy distributions, and photometric/spectroscopic redshifts, and c) derived rest-frame parameters (e.g. stellar masses, star-formation rates). We will also disseminate the software specifically developed for our analysis, using VO-compliant services. We ourselves propose to use this unrivalled database to address several of the key outstanding issues in present-day extragalactic astronomy, Finally, we will use the gained experience to maximise the scientific return from the next generation of space surveys, especially ESA’s planned EUCLID Deep survey."