When do we become adults? What does it mean to grow up? And what are the experiences that propel us forward - or keep us stuck? These are the questions that journalist Moya Sarner sets out to answer as she begins training as a psychotherapist.

But as she delves further into her own mind and others', she soon realises that growing up is far from the linear process we imagine it to be. So begins a journey of discovery into what growing up really involves, and how we do it again and again throughout our lives.

From early adulthood through to old age, When I Grow Up examines each life stage, interrogating the traditional markers of adulthood and finding new ones. Through conversations with grown-ups from all walks of life, and through her own experiences and training, Sarner probes deep into our psyches to discover how we grow and develop, and what we need to thrive throughout our lives.