In 1983, Harada returned to Tokyo and created several other well-known chamber music ensembles, including NADA and Mito Quartet. Since his debut as a conductor with the New Japanese Philharmonic Orchestra in 1988, Koichiro Harada has increasingly focused on this area of activity. He conducts the Philharmonic Orchestras of Osaka, Hiroshima, Kyoto, Tokyo, the Orchestra Ensemble Kanazawa, the Kyushu Symphony Orchestra and many others.
For his records, Harada received the "Stereo" and "Gramophone" Magazines Award for the Best Record of the Year. Grammy Nominee.
Harada is currently the Head of the String Instrument Department at the Toho Gakuen School of Music and the Music Director of the Ishikawa Music Academy in Japan. Koichiro Harada was invited to Juries of many major international competitions: the Queen Elizabeth Competition in Belgium, the Indianapolis Violin Competition, the N. Paganini Competition in Genova, and the Henryk Wieniawski Violin Competition in Poland. In 2005, he was the President of the Jury of the Long and Thibaud International Violin Competition in Paris.