Gwendoline Smith is a clinical psychologist, speaker, blogger and the author of the books The Book of Feeling Blue (2023), The Book of Angst (2022), The Book of Overthinking (2021) and The Book of Knowing (2020), Depression Explained (2002) and Sharing the Load (1996). She also goes by the name Dr Know. Born and raised in Chatham, Kent, she now lives in Auckland, New Zealand.