As a conductor he has performed in concerts at the Herodeion at the Athens Festival, the Athens Concert Hall at the University of Tubingen and the Berlin University of the Arts.
As a composer,,Costas Eliades has composed many works for chamber music ensembles as well as for symphony orchestra. He is involved in composing for theatre and documentary films as well as arranging, transcribing and adapting works for guitar and other ensembles. He was responsible for the reconstruction of the score of the works by M. Hadjidakis "The Cursed Snake" and "Six Folk Paintings" for two pianos.
His orchestrations have been performed by the Camerata of the Friends of Music at the Athens Concert Hall, by the Patras Orchestra at the Athens Festival and by the String Orchestra of the Municipal Conservatory of Patras. His works have been performed by the Filarmonica Paul Constantinescu, the Youth Orchestra of the Third Programme of Greek Radio, the Modern-e-Quartet, the Athens Bridge Quartet, and the DissonArt Ensemble in concerts in Athens and at the Athens and Thessaloniki Concert Halls, as well as abroad. In addition, his works are released on CD by Motivo and Ekfrassis Production.
As a guitarist he was a member of the ''Trio Polychordo'' with which he has been awarded in the second Panhellenic Chamber Music Competition, organized by HELEXPO in Thessaloniki.
He has given many concerts in Greece and Germany and participated in many festivals: First International Festival of Patras, First Music Festival of Nafpaktos, First Concert Cycle of the Third Programme of the Greek Radio, Concert Cycle of the Municipality of Patras, Sunday Music Mornings at the Athenaeum, Festivals of the Municipality of Heraklion, Municipality of Lefkada, Municipality of Samothrace, etc.

He has recorded for the Second and Third Program of the Greek Radio. He has performed as a soloist with the Patras Orchestra, the Jena Symphony Orchestra and has participated in the Athens State Orchestra.
He presented the first performance of works by Greek composers (S. Zanna, O. Amiralis, I. Haliasa), as well as the concert for guitar and symphony orchestra by E. Triantafyllou in a concert for Greek music organized by the Weimar Music Academy.
As a producer he was the main organizer of the innovative Music Mornings at the Athenaeum. He has organized festivals, concert cycles and concerts in Greece and abroad, as well as recordings. For many years he was the artistic director of the annual concert cycle of the Municipality of Nea Makri. He is also the artistic director of the Summer Music Camp that takes place every year, focusing on musical ensembles and orchestra.
As a professor he teaches at the National Conservatory of Athens and at the Argyroupoli Municipal Conservatory, where he has been artistic director since 2022.
He is a regular member of the Union of Greek Composers.
Costas Eliades studied guitar with Vangelis Bountounis, cello with Dimitris Gouzios, composition with Michalis Traylos and orchestral conducting with Anastasios Simeonidis. He has attended guitar seminars with Abel Carlevaro, Leo Brouwer, Roberto Aussell, Evangelos Asimakopoulos. Finally, he is a graduate of the Agricultural School of Athens.