• Oakley, Robin 1, 2
• Observer (newspaper) 1
• O’Cathain, Baroness Detta 1, 2, 3
• official secrets 1
• O’Friel, Brendan 1
• Ogilvy, Sir Angus 1, 2
• Old Vicarage (house) 1
• Onslow, Cranley 1
• Ormerod, Ben 1
• OSPA (Overseas Service Pensioners’ Association) 1
• OTC (Officers’ Training Corps) 1
• OUCA (Oxford University Conservative Association) 1, 2, 3
• Owen, David 1
• Oxford University 1