1. INTRODUCTION  
2. MULTI-WAVELENGTH DATA  
2.1. SCUBA-2 Data  
2.2. Ancillary Data  
3.2. Counterpart Identification  
3.3. Unidentified Sources  
4. DERIVING PHYSICAL PARAMETERS  
4.1. AGN Contamination  
4.2. Redshift  
4.3. Stellar Mass  
4.4. Infrared Luminosity  
4.5. Dust Properties  
4.6. Ultraviolet-continuum Slope and Ultraviolet Luminosity  
4.7. SFRs  
5. THE NATURE OF SCUBA-2 450-µm-SELECTED SOURCES  
5.1. The Star-formation Main Sequence  
5.2. Td – L Correlation IR  
5.3. IRX–β UV  
6. INFRARED LF  
6.2. Likelihood Method  
6.3. Comparison with Other Observations  
6.4. Comparison with Models  
7. THE OBSCURED STAR-FORMATION HISTORY  
8. SUMMARY