Also look at the IREB® CPRE page, the IREB® About page and the IREB® Exams page
The REQB® creates the syllabi, defines the rules for accreditation and certification and manages all the activities of some international Working Groups, that facilitate the development of REQB® for the cooperative design of syllabi, exam rules, processes, etc. The REQB® Working Groups ensure the development and the spread of the knowledge according to the most up-to-date needs of the profession.
The Member Boards act in the local communities as direct contacts to professionals and organizations interested in the REQB® scheme; they translate syllabi in the local languages, accredit training providers and perform exams (directly or through examination bodies that are thus represented in dotted lines).
Training providers create the course material in alignment with syllabi and perform training to those professionals interested in such service; taking a training course is not a pre-requisite for sitting in an exam (this is the reason why the arrow from training providers to certified requirements engineers is dotted).