Translation providers (individual translators, revisers, translation departments and agencies) as well as their clients, rely more and more on translation quality assessment (TQA) for various reasons. While they all agree on the need for a translation to be "good" or "acceptable," the definition of “good” translation and the criteria for determining it remain subject to continuous debate. Various national and international translation standards exist nowadays, but how efficient are they? What are their shortcomings? What difficulties hinder elaborating and using a standard model for translation quality assessment?This research paper explores the definition of "good" translation, the existing standards for quality assurance and quality control and evaluation, with examples of some models used in assessing the quality of translations and their application.