Chapter 2 provides a theoretical background to the thesis which includes basic X-ray scattering phenomena, anomalous scattering, X-ray diffraction and the theory of protein crystallography. The second half of the chapter is dedicated to describing the standard programs used for the analysis of protein crystal diffraction data. Also described is a program written during the period of study which is used for the determination of anomalous scattering factors from fluorescence measurements. Chapter 3 describes the experimental apparatus used for the MAD experiments. Both existing apparatus and apparatus designed and built for the purposes of this work are described. The fourth chapter contains details of the MAD experiments which were performed on a test protein; methods, preliminary data analysis and results are presented together in this chapter. The final chapter places the work in context and discusses its relevance to the future of the MAD method.