On 31 August 2026 I will step down as ESO Director General after 9 years of service. It will also be the date of my retirement as Research Professor of the Spanish Research Council (CSIC).  It is almost 20 years since I started to participate in ESO's governance, after contributing to the negotiations towards the accession of Spain, first as ESO Council observer (2006), then Council delegate (2007-2011), Council Vicepresident (2011), Council President (2012-2014), ALMA Board member (2009-2014), OPC chair (2016) and finally as Director General during the last nine years (2017-2026).

ESO is an amazing organisation, with fantastic achievements during its almost 64 years of history. After a commendable effort by astronomers from various European countries, ESO was established in 1962 as an intergovernmental organisation in a time when US observatories were way ahead of those in Europe. It was challenging to retain talent in Europe unless competitive facilities would become available; ESO was an important gamechanger in this strategy. First the 3.6 m ESO telescope in La Silla, later the NTT leading to the VLT in Paranal and a bit later the world-unique VLTI made ground-based observational astronomy in Europe flourish and become world-wide competitive. ALMA as an "equal to equal" partnership between ESO, NSF and NINS, resulted in a resounding success. At the turn of the century, when astronomers from all around the world were advocating for extremely large telescopes, ESO took its time to prepare its options with the support from the community, while other two international projects (GMT and TMT) progressed on their early stages. Today, ESO’s ELT is more than 75% complete, and around a decade ahead of the other ELT projects. In all likelihood, ESO's ELT will collect the low-hanging fruit only accessible through this new generation of telescopes -a pride for ESO and its supporting community.

In my time as ESO DG I have enjoyed enormously the countless scientific breakthroughs achieved by the scientific community using data from ESO facilities. At a stable rate of around 1,100 refereed papers per year generated by ESO data, it is very difficult to choose what to underline.  Out of those almost 700 come from Paranal, 200 from La Silla, and almost 300 from ALMA (across the Partnership it is more than 500 yearly). Some 300 papers make use exclusively of archival data.

These being only numbers, do not make at all justice to the many discoveries enabled. I had enjoyed the privilege during my mandate to live with joy the award of the Nobel Prize in Physics to three members of the ESO scientific community: Michel Mayor and Didier Queloz in 2019 and Reinhard Genzel in 2020. During this period, and thanks to ESO's facilities and the talent of our community, Black Holes have been imaged, gravitational redshifts and Schwarzschild precession around Sgr A* have been measured, planets have been discovered in habitable zones, protoplanetary disks around young stars have been imaged and planets forming there have been witnessed, the structure of exoplanet atmospheres could be measured, interstellar "visitors" to the solar system studied, convective surfaces of red giants were resolved, kinematics and resolved chemical abundances of distant galaxies could be obtained, and a galaxy at z=14 discovered by JWST was resolved, its redshift, oxygen abundance and mass measured. With infinite apologies to all colleagues who produced many other wonderful results not in the above list, I will additionally pick up one of my favourites: witnessing the disk-jet connection around the black hole at the centre of M87.

I also had the privilege of accompanying ESO during the time when our world-class observatories La Silla Paranal Observatory and ALMA underwent important developments and upgrades. MATISSE, IRLOS+, CRIRES+, NIRPS, GRAVITY+, SoXS, 4MOST and MOONS saw first light during the last 9 years. In 2017, ALMA Band 5 was completed and integrated, while Band 2 will be operational in the next Cycle. Lots more instruments and upgrades are in various phases of development. And of course, also the very challenging ELT instruments, MICADO (first light instrument) and METIS being in Manufacturing, Assembly, Integration and Test (Preliminary Acceptance in Europe for both is planned in 2029), MORFEO following a couple of years later, and new and solid version of HARMONI which will come on line around 2035. The ELT second-generation instruments ANDES and MOSAIC are making their way towards Preliminary Design Review.

In addition to world-class science and world-leading facilities, ESO is also very active in engagement with its multiple stakeholders. First the scientific community, including the institutions which partner together with ESO to develop instrumentation for our telescopes. Next, our industrial partners, to which we often request meeting very challenging requirements in the manufacturing of our sub-systems. At the end, we get our components, and generate know-how in the companies, an added value for our eco-system. Importantly, the Governments and agencies of our Member States, who have unfailingly supported ESO, "through good and bad weather". They believe in this organisation, because we commit and deliver in good coordination with the scientific community. Finally ESO also engages with society at large; we want everyone to feel proud of ESO and our achievements, so communicating what we do through many channels (including the ESO Supernova Planetarium and Visitor Centre) and its value is a priority for ESO. When Paranal was under threat because of the plans to establish a huge industrial compound very close to the site, scientists, and society alike raised red flags. Such threads will continue in the future, so cultivating engagement at all levels is vital for ESO.

I want to say a word about Chile, the Host State of ESO telescopes, with which we have international agreements since 1963. All our telescopes today are in Chilean soil, in some of the world's best sites for astronomical observatories. Today Chile has a vibrant and internationally recognised astronomical community, with which ESO maintains a solid partnership. Scientific collaborations between Chilean and Member State scientists and institutions,exist and I sincerely hope that engagement in other fronts will only grow in the future.

It has been a privilege accompanying ESO during 20 years in different roles, and the last 9 in a leading role. We experienced many challenges: a period of social unrest in Chile, a pandemic, a period of large inflation, war in Europe and a world where International Cooperation does not appear to be a broadly supported solid value anymore. Despite this, ESO is healthy, world-leading and with a brilliant future, in which the ELT is soon to finalize construction and start operations, and in which the next major ESO project, to start taking shape under the Expanding Horizons initiative, will consolidate European leadership in astronomy. I will enjoy seeing it flourishing further, under the lead of my colleague Andreas Kaufer.