Mr Day qualified from St George's Hospital Medical School in 2000 and trained in the South West Thames region. During his training he undertook his MD research in Enhanced Recovery after colorectal surgery and was one of the Ethicon laparoscopic colorectal fellows. 

He joined SASH in 2015. He specialises in laparoscopic colorectal cancer surgery and is the lead for the new colorectal robotic programme. 

Mr Day has a special interest in rectal cancer management and enhanced recovery after surgery. He is the departmental lead for enhanced recovery and mortality and sits on the council of the Association of Laparoscopic Surgeons of GB & I.