The Law 1905/1990 introduced in the Greek legislative framework the concept of "Agency of business requirements" to which the widely spread modern institutions of factoring and forfaiting were subordinated, which constitute the most efficient source of working capital for a business. Within this framework, this work, having as its main object of study factoring and incidentally researching forfaiting, presents in detail both the technical aspect and the economic significance of the institution, as well as its legal dimension and is addressed to every legal professional, bank and factoring company, as well as to every business interested in learning what it is, how it is exercised and what it can expect from its implementation.