The Alexander S. Onassis Public Benefit Foundation's activities are multifarious, focused on very important areas such as culture, education, environment, health and social solidarity.

Within the framework of its activities for the promotion of culture, the Foundation created the Onassis Cultural Centre on Syngrou Avenue in Athens, totally dedicated to arts and culture. The foundations of the Onassis Cultural Centre were laid in the year 2000 and the building operated for the first time in November 2010 by hosting the international conference The Athens Dialogues.

The Onassis Cultural Centre is Athens' new cultural space, open and accessible to everyone, hosting theatre, dance, music, visual arts events and letters. Its mission is to promote contemporary culture, to support young Greek artists, to cultivate international collaborations, to educate children and people of all ages through life-long learning. The new cultural space was officially inaugurated in December 2010.

The Athens Dialogues is a research project in progress of the Alexander S. Onassis Public Benefit Foundation, which started with the organization of an international conference at the Onassis Cultural Centre in November 2010 and is being continued with various post-conference events.

The project aims to explore the relationship between Greek culture and the modern world. The perspective of the Dialogues revolves around a diachronic and interdisciplinary approach, taking into consideration not only the views of the humanistic sciences but also the ones of social and exact sciences.

The Athens Dialogues of 2010 focused on 6 themes (Identity and Difference, Stories and Histories, Logos and Art, Democracy and Politeia, Science and Ethics, Quality of Life) and was co-organized in collaboration with 8 leading world class academic institutions (Academy of Athens, Accademia dei Lincei, Austrian Academy of Sciences, German Archaeological Institute, Institut de France, Centre for Hellenic Studies of Harvard University, University of Oxford, Stanford University).

The next stage of the Athens Dialogues project will focus on a general topic entitled The challenges of tomorrow as today's responsibilities which will be treated in four thematic sessions: Democracy – Education – Natural Sciences – Art.

The Onassis Foundation disseminates Greek civilisation abroad and specifically to the U.S.A. and Canada, through the affiliate foundation at the Olympic Tower in New York, which organizes conferences, a major archaeological exhibition every year, and a programme of visiting Professors to Universities of North and South America and Canada. In this context, the Foundation undertook the establishment of the Onassis Library for Hellenic and Roman Art at the Metropolitan Museum of Art in New York, the renovation and equipment of the libraries of the National Archaeological Museum, the Christian and Byzantine Museum and the Benaki Museum in Athens, the architectural preservation and restoration of sites and buildings around the world, as well as countless other endeavors related to arts and culture.

Among its other activities, the Foundation awards scholarships to Greeks for postgraduate studies in Greece and abroad and to non-Greeks for research and postgraduate studies in Greece. Until 2010, approximately 4,411 scholarships have been awarded to Greeks and 683 to foreigners. The Scholars Association, with the active involvement of approximately 1600 former scholars and the financial support of the Onassis Foundation, organizes conferences, lectures, cultural and scientific events.

In the fields of social solidarity and health, the Foundation donated to the Greek state in 1992 the model Onassis Cardiac Surgery Centre (OCSC). The 127-bed capacity OCSC is the first hospital in Greece fully certified in the departments of adult and pediatric heart surgery and cardiology, the only certified hospital in Greece for heart and lung transplantations, maintaining of the best survival rates internationally. Other public benefit projects of the Foundation include financial support to organizations such as ELPIDA for the establishment of cancer hospital for children, and the Hellenic Society for Disabled Children (ELEPAP).

Another important aspect of the Foundations work is the awarding of international prizes, since 1978. Bestowed on individuals or organizations in the fields of culture, social achievement and the environment, were redesigned in 2008, to include the following Onassis International Prizes, closely related to contemporary international issues and challenges:

1. In Shipping, Trade and Finance, in collaboration with the City of London and Cass Business School of the City University, London.

2. In Law and in Humanities, in collaboration with the Institute of France.

3. For the Protection of the Environment, in collaboration with the City of Hamburg, European Green Capital for 2011

4. Hestia Onassis International Prize in Immigrant Integration and Human Development for a period of three years, in the framework of the Civil Society Days Forum of the 3rd Global Forum on Migration and Development in Greece, organized by the Foundation.