Aristotle's theory of modal syllogisms has been a source of trouble to interpreters almost from the day of its enunciation. This chapter offers the result of a systematic study of Aristotle's theory of modal syllogisms. The aim of this inquiry is to answer three questions: What did Aristotle himself have in mind in his theory of modal syllogisms? Is his development of this branch of logical theory consistent with his concept of modality, or is it replete with mistakes, as modern critics have alleged? Is Aristotle's concept of modal syllogisms adequate as a theory of modal inference which serves the purposes of his own conception of modality, or does it fail in its own purposes, as was alleged by Aristotle's immediate peripatetic successors? In brief, authors’ aim is a synoptic exposition and evaluation of Aristotle's theory of modal syllogistic. A cursory glance at the tabulation shows clearly why Aristotle assigns a preferred status to the first figure of syllogism.