This article reviews the post-Second World War literature on explanations for Australia's immigration program. It discovers three main schools of thought based on net pull factors: the official explanation and two unofficial explanations which focus on migrants as workers and on migrants as consumers. However the growing importance of net push factors after 1974 means that some of this work is less relevant today. Explanations focusing on net push factors have yet to cohere into a distinct perspective (or perspectives) but some research has been done on chain migration and family-based migration strategies, asylum seekers, temporary movement, and migration and the law. Immigration research is sometimes controversial and politicized. While intellectual integrity must always take priority, the values of civility and tolerance are also important.