The paper studies the productivity of eight Greek verb-forming suffixes (-áro, -éno, -évo, -íno, -ízo, -(i)ázo, -jázo and -óno) in a corpus of 4,143,583 words. The corpus used comes from the Corpus of Greek Texts and includes all text types found in it in the same proportion. Our study follows similar research on other languages, investigating frequency and morphological productivity with a corpus-based methodology. The productivity of the suffixes was studied in the corpus as a whole, across its two subcorpora of written and spoken registers and across and within the text types included in the corpus. Three main sets of suffixes were identified: (a) the very productive -ízo and -óno, (b) the moderately productive -évo and -áro and (c) the least productive or unproductive -iázo, -jázo, -éno and -íno. The results from the study of text types suggest that the degree of productivity of each suffix is influenced by the text type in which it occurs. Quantitative evidence drawn from the measurement of productivity, by means of vocabulary growth curves and related methods, was combined with qualitative evidence on the semantic and other properties of verb-forming suffixes. On the basis of our results it cannot be argued that there is a default suffix for verb derivation in Modern Greek; it is rather suggested that the two most productive suffixes, -ízo and -óno, are used in Greek in a more or less complementary way, since they show a different preference for meanings and text types.