Every four years, beginning in 1984, the Mathematics Education Research Group of Australasia (MERGA) produces a review of Australasian research in mathematics education. The authors of the chapters in this volume have summarised and critiqued research conducted during the period 2004-2007. The research foci for the period are reflected in the chapter titles. Working under tight funding opportunities and the shadow of demanding research accountability measures, the research undertaken has, nonetheless, been rigorous, far-ranging, and at the cutting edge. In bringing this regular review of the best of Australasian mathematics education to a broader international audience for the first time, readers will recognise the outstanding contributions made by Australasian mathematics education researchers and the potential their findings have to inform and direct future directions in the field.