Compiling information for the Yearbook involves a year-round process of research and editing. Proofs of organization descriptions are sent out by post, email and fax for the organizations themselves to correct. The average response rate is 35%, ensuring highly reliable information. Priority is normally given to information received from the organizations themselves, and every effort is made by the editors to check this information against other sources.
Proofs are supplemented with information from websites, annual reports, newsletters and other documents. Organizations that do not respond to the proofs are followed up with telephone calls, or researched via the Internet.