Economou influenced the evolution of theoretical physics in Greece since the late 1970s, as described in detail in a special volume published in 2000, in Physica B, on the occasion on his 60th birthday.

During this period, he was given the opportunity to attend a number of graduate level physics courses at the "Center for Advanced Studies and Philosophy of Science" which was organised at the National Centre of Scientific Research "Demokritos".

Before leaving for the U.S., in February 1966, he married Athanasia Paganou[8] and they have a daughter, Sophia Economou,[9] who is professor of physics at Virginia Polytechnic Institute and State University.

Two months later he passed the qualifying exams, ranking first among his classmates, which made it easy[10] to be accepted as a PhD student in the group of Morrel H. Cohen.

As the first chairman of the department[12] he established the bases in the Physics  curriculum and he was instrumental[2] in hiring high quality faculty at the University of Crete.

He was and remains a strong advocate on topics related to the negative influence of political parties and direct involvement of students in the normal operation of the universities.

Economou was the prominent figure of a group of five Greek scientists from abroad, namely Fotis Kafatos, Dionysios (Dennis) Tsichritzis, Grigoris Sifakis[16] and Peter (Panagiotis) Lambropoulos,[17] who planned the idea[18] and with the help of the Minister of Research and Technology Georgios Lianis, convinced the Greek Government to create[2][4] the first three Institutes of the Research Center of Crete (RCC; Ερευνητικό Κέντρο Κρήτης – ΕΚΕΚ) in Heraklion.

In 1986 Skinakas Observatory, jointly supported by RCC, the University of Crete and the Max Planck Institute for Extraterrestrial Physics (Germany) also commenced its operations.

Science and Technology Parks were established connected to the institutes in Heraklion, Patras, and Thessaloniki and respective buildings with European funding were erected.

He was awarded[14] the title of emeritus professor at the University of Crete and he continues to teach and remains active in research at the department of physics.

The collaborative research on negative index metamaterials led by Economou and Soukoulis, including scientists from Imperial College (Sir John Pendry), Karlsruhe Institute of Technology and Bilkent University (Ekmel Özbay), was recognized with the award of the European Union Descartes prize for collaborative research in 2005.