Browse People - O
- O'Connell, Maude, Trade Unionist
- O'Dea, Peter, Trade Union - Activist
- O'Neill, John Henry (1888 - 1971), Trade Union - Official
- O'Neill, Wilfred Michael (1900 - ?), Trade Union - Official
- Origlass, Nicholas (1908 - 1996), Trade Unionist
- O'Shea, Clarence Lyell, Trade Union - Official
- Owens, Joseph, Trade Unionist and Trade Union - Official