1 INTRODUCTION  
2 DATA  
2.1 The Cluster Catalogue  
2.2 Optical Data: the SDSS DR12  
2.3 Infrared Data: WISE  
3 ANALYSIS AND RESULTS  
3.1 Cluster Sub-samples  
3.2 Optical Colour Distributions  
3.3 Infra-Red Colours and Detection of Star-forming BCGs  
3.4 Stellar Masses  
4 DISCUSSION  
4.1 The Optical Colours of BCGs  
4.2 The Star Formation Activity in BCGs  
4.3 AGN Detection in BCGs at IR Wavelengths  
4.4 Blue BCGs: are they all star forming?  
4.5 Stellar Mass Growth  
5 SUMMARY AND CONCLUSIONS