1 INTRODUCTION  
2 THE SUMO PROJECT  
3 DATA ACQUISITION, REDUCTION, AND STANDARDIZATION  
4 PHOTOMETRIC SELECTIONS AND COLOUR-MAGNITUDE DIAGRAMS  
5 THE $c_{\mathrm{U,B,I}}$ INDEX AS A NEW DIAGNOSTIC FOR MULTIPLE STELLAR POPULATIONS  
6 DISCUSSION: THE CHEMICAL PROPERTIES OF MULTIPLE SEQUENCES  
7 CONCLUSIONS