EAGLE is an instrument under consideration for the European Extremely Large Telescope (E-ELT). EAGLE will be installed at the Gravity Invariant Focal Station of the E-ELT. The baseline design consists of 20 IFUs deployable over a patrol field of ~40 arcmin2. Each IFU has an individual field of view of ~ 1.65" x 1.65". While EAGLE can operate with the Adaptive Optics correction delivered by the telescope, its full and unrivaled scientific power will be reached with the added value of its embedded Multi-Object Adaptive Optics System (MOAO). EAGLE will be a unique and efficient facility for spatially-resolved, spectroscopic surveys of high-redshift galaxies and resolved stellar populations. We detail the three main science drivers that have been used to specify the top level science requirements. We then present the baseline design of the instrument at the end of Phase A, and in particular its Adaptive Optics System. We show that the instrument has a readiness level that allows us to proceed directly into phase B, and we indicate how the instrument development is planned.© (2010) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.