1 INTRODUCTION

2 THE SDSS SAMPLE  
2.1 Selection  
2.2 Spectral Classification  
2.3 The M subdwarf sample  

3 NEW BINARY SYSTEMS  
3.1 Wide common PM binaries  
3.2 Partially resolved binaries  
3.3 Binary fraction of RSDs  

4 BINARY SYSTEMS OF NOTE  
4.1 G 224–58 AB (esdK2 + esdM5.5)  
4.2 SDSS J210105.37 − 065633.0 AB (esdM1+esdM5.5)  
4.3 Three carbon subdwarfs in binary systems  
4.4 Six RSDs companion to WDs  
4.5 An esdK7+WD spectroscopic binary  

5 SUMMARY & CONCLUSIONS