The founders of Deltos Publishing, Kleanthis Arvanitakis and Frosso Arvanitaki, are the authors of the course Epikinoniste Ellinika (course books and workbooks) and Communicate in Greek for Beginners, the English version of the first level of the course in question. They are also the authors and co-authors of some of the other books published by Deltos Publishing. Τhey have long experience in teaching Modern Greek to groups of speakers of other languages.

The other authors, Maria Aroni, Lily Exarhopoulou, Yannis Karadimos, Neni Kolethra, Argyro Margariti, Yanna Nella, and Lelia Panteloglou currently teach or have taught Greek as a foreign language. They are, consequently, fully aware of the concerns and interests of the learner of Modern Greek.