MAGMA: Statistical microarray analysis made user-friendly We have implemented MAGMA, a powerful but easy-to-use web application for the statistical analysis of microarray data analysis. For inexperienced users, MAGMA quickly generates data overview plots, performs data normalization and evaluates differential expression. Every processing step is tracked in an R-Script, that documents the processing for the user, and that allows users familiar with R to reproduce the data processing and conduct further, advanced analysis using R and Bioconductor. MAGMA is implemented using a modern Java-based architecture. It is highly modular and easy to maintain and extend. The web frontend is generated using Java Server Faces, the application logic is implemented as a Java servlet, and all statistical processing is performed using R and Bioconductor. Rserve provides the smooth integration of both Java and R. MAGMA's strength lies in the intuitive user interface that allows biologists to run complex statistical tests in microarray data. Application: http://www.magma-fgcz.unizh.ch Source code: Available soon.