1. Introduction  
2. Observations and Data Reduction  
2.1. X-ray Data and the Updated SMC Survey  
2.2. The Mid Infrared Sample & the ALLWISE Data  
2.3. HMQ/MILLIQUAS Catalogues  
2.4. Correlation of the XMM-Newton and ALLWISE/HMQ/MILLIQUAS Catalogues  
3. Results and Discussion  
3.1. The X-ray Selected Sample: Characterisation  
3.2. Correlation with the SMC X-ray Point Source Catalogue from 2013  
3.3. Identification of Near-infrared Counterparts  
3.4. Multi-wavelength Properties  
3.5. Identification of New Candidates  
3.6. Optical Spectroscopy of New Candidates  
3.7. Comparison of the Sample with the Expected Population of AGN  
4. Summary & Conclusions