This book reports an experimental investigation on the effects of a new type of cooperative learning method namely 'Competitive Team-Based Learning' (CTBL), developed by Dr Hosseini (2012) at Mashhad Education Office in Iran, and 'Student Teams-Achievement Divisions' (STAD), developed by Slavin (1977) at Johns Hopkins University, in the US, on the reading comprehension of Iranian EFL intermediate students. The results of the study showed that CTBL was more effective than STAD in improving the reading comprehension ability of Iranian EFL intermediate students.