Panagiotis Theodossiou was born in Athens in 1964. At an early age he studied piano with Efi Agrafioti and went on to study Harmony, Counterpoint, Fugue and Composition with Michalis Travlos, Michel Merlet and Theodoros Antoniou; Jazz piano and Improvisation with John Terezakis. He has also studied Theology at the Kapodistriakon University of Athens.

He has been teaching Piano, Musical Theory, Harmony and Counterpoint at musical schools in Athens for many years. Other activities include his contribution as a co-founder and article-writer in the Greek musical magazine "Ta Moussika" and in the web magazine "TAR" (www.tar.gr ) while he is also a producer on the Greek radio.
He has been in charge of the Music Department of "Geitonas School" of Athens for many years and still teaches and conducts the choir and orchestra of the institution.

Panagiotis Theodossiou is a member of the Greek Composers Union.

His composing activities includes many works for piano, chamber, choral and orchestral music and music for the big screen as well. His love for and interest in orchestration and jazz arrangement led him to write many symphonic transcriptions on classical and contemporary piano works and found small ensembles in witch he participates as a pianist.

His works have been performed all over the world (Los Angeles, Boston, Philadelphia, Hague, Athen, Patmos, Konstantinople)by distinguished artists, such as: Michel Arrignon, Stathis Kiossoglou, Reima Raias, Giannis Sabrovalakis, Katerina Tsents, Dimitris Magriotis, Lorenda Ramou Spiros Kontos, Kostis Theos, Angelica Kathariou, Konstantinos Papadakis, Andrea Hemmenway and others as well as orchestral ensembles as "ALEA III" under Th. Antoniou, Orchestra of Colours under Miltos Logiadis, "Hellenic Ensemble of Contemporary Music" under Iakovos Konitopoulos, "Athens String Orchestra", the "Bridge Quartet", the vocal ensemble "Philodos", the ensembles "Duo Pianismo", "Q innegal" Wind Quintet, "Meteora Ensemble", "Trio Casals" and others.

He has recorded many of his works on CD, and participated on CD recordings of works by Greek Composers.