Despite the well-established benefits of cooperative learning, implementation remains a challenge. This research aims to document these challenges at the elementary school level, drawing on teachers' beliefs regarding learning as well as the difficulties teachers report. Results indicate that the most frequent instructional strategies reported are traditional ones such as teacher-monitored, collective class discussion, transmission and individual work. The use of these last two is particularly associated with teacher beliefs that learning derives from teacher-delivered knowledge. In general, this research found that teachers do not perceive cooperative learning as very easy to implement; over 40% introduce it occasionally and only 33% use it routinely. Teachers reported that they are particularly ill at ease with embedding cooperative learning in the curriculum, finding the time required for cooperative learning and evaluating pupils when using cooperative learning. Results underline that, in addition to teachers' learner-orientation beliefs predicting the use of cooperative learning, the more teachers report difficulties in embedding cooperative learning into the curriculum and finding time for it, the less they say they actually implement it. Contributions to teacher education programmes are discussed in the light of these findings.