h. d. karunaratne wrote many books using the exposure and insight he gained over the years in japan, titled, a journey in harmony: sixty years of japan-sri lanka relations (2012), internationalization of sri lankan entrepreneurship: a study of sri lankan immigrant entrepreneurs in japan (2009) and distant neighbors at work place: a study of sri lankan migrant workers in japan (2007). h. d. karunaratne has been a member of japan society of international development, graduate school of international development , nogoya university alumni association, and east asian economic association. and also he has been functioning as a member of south asian federation of japanese graduates’ alumni association.