Dr. Harry Barry seeks to address the deficit in public knowledge relating to the understanding of mental health. He presents a unique approach to the subject based on a colour-coded flag system: the Green Flag denotes the normal mood system, the Red Flag stands for depression, the Yellow Flag for anxiety, the Purple Flag for addiction, and the White Flag for suicide. He discusses each of the 'flags' in turn and answers many commonly asked questions about mental illness and the ways in which it is treated by GPs, specialists and others. He offers advice to those suffering from this illness and the people close to them; above all he seeks to dispel the stigma that continues to surround mental illness.