CANNES, France --- Thales Alenia Space is ready to deliver the high-resolution (HR) optical imaging instrument for integration in the first Pleiades earth observation satellite.>> The Pleiades project is part of ORFEO*, a joint Franco-Italian initiative by the countries' national space agencies CNES and ASI, marking a major technological advance in optical earth observation systems. The dual-technology program addresses both military and civil needs for European users, including mapping, volcano monitoring, geophysical and hydrology studies, urban planning, etc. As prime contractor for the Pleiades system-in particular the ground segment-CNES selected Astrium as satellite prime contractor and Thales Alenia Space for the imaging instruments.>> The Pleiades optical high-resolution imaging instruments offers enhanced resolution of 70 cm over a wide swath (20 km) in both the visible and near infrared bands. This very high resolution instrument also introduces significant innovations such as the highly-integrated detection sub-assemblies (SEDHI), while also reducing volume three-fold compared to previous generations. The instrument provides very high dimensional stability thanks to a concept combining a carbon/carbon structure (material insensitive to moisture and with a very low coefficient of thermal expansion) and Zerodur mirrors. To optimize in-flight performance, the instrument has an innovative thermal refocusing system, eliminating the need for a complex mechanism.>> The absence of this mechanism plus the satellite's own enhanced performance (satellite pointing/tilting capabilities, downlink transmission rate of 450 Mbit/s) means a significant increase in mission performances.