There is a nascent movement towards evidence-based practice in education in Australia, evident in Federal and State education documents, if not in classrooms. Such a classroom-level outcome would require a number of conditions to be met. One of the critical requirements is that teachers be provided with knowledge and training in practices that have an acceptable evidence base, in other words to know "what works". Many reformers pin their hopes on systematic reviews to provide the information. However, it is becoming increasingly apparent that this expectation may not be easily met, especially in the short term. This paper considers some of the recent issues that have muddied the waters.