Northern Lights on PISA 2003 ­ a reflection from the Nordic countries is a successor to Northern Lights on PISA ­ unity and diversity in the Nordic countries in PISA 2000, published in 2003. As with the first report the chapters in the present publication are written by Nordic researchers looking mainly at the PISA 2003 results from different angles and with special emphasis on what can be learned from analysing results from the Nordic countries. The report is not just for researchers. The main goal has been to communicate interesting findings to policy makers and educators. Another important aim of the report has been to show that educational achievement in general cannot be understood in terms of simple relationships between single variables. Educational results are multivariate in nature and simplistic conclusions should be treated with suspicion.&nbsp, There are similarities between our Nordic countries which can help us all understand better how our education systems work.The differences between us are also illuminating in many respects.