1 INTRODUCTION  
2 THE DATA: PANCHROMATIC OBSERVATIONS OF ELAIS-N1, BOÖTES AND THE LOCKMAN HOLE  
3 THE RADIO LUMINOSITY FUNCTION OF STAR-FORMING GALAXIES  
4 RELIABLE CONVERSION OF $L_{150\mathrm{MHz}}$ TO SFR  
5 THE COSMIC STAR FORMATION DENSITY HISTORY  
6 CONCLUSIONS