'When Dan died, there was so much I wished I'd known. I'll never know whether knowing any of the things I didn't know, or doing any of the things I didn't do, would have been enough to keep Dan safe in that moment of decision, but if in reading this book my gaps are filled for you, and a difference is made for your children, then that will be more than good enough for me.'

When Daniel Spargo-Mabbs was 16, he went to a party and never came home. The party was an illegal rave and Daniel - a bright, popular, big-hearted prom king - died from a fatally strong overdose of MDMA.

I Wish I'd Known is the book Dan's mother Fiona - co-founder of the leading drug education charity the Daniel Spargo-Mabbs Foundation - wishes she'd had as her intelligent, inquisitive child entered his teenage years. Because however you parent, and whatever you do, your child is very likely to be at some time or other in a situation where they have to make a decision about drugs. What if that decision is 'yes'? Do they know what the risks are? Do they have practical strategies they can bring to bear if things go wrong?

Use of illegal drugs is on the rise among teenagers, and accessing advice and support to help navigate this landscape is critical not just for them, but for you as a parent. I Wish I'd Known explores the risks and effects of the substances young people are most likely to encounter, and the legal pitfalls that may leave their own lasting legacy. It explains the way the adolescent brain makes decisions and manages risk, and gives insight into how to manage important conversations through these often tricky years. There are practical strategies for staying safe, information on reducing harm, and 'talking points' providing ideas for things to do, to talk about, look at, look up or consider.

Throughout the book, Daniel's story - his life, his death, and what happened afterwards - not only provides a compelling reminder of the importance of those conversations, but also serves as a beautiful, unforgettable eulogy to a son, brother, boyfriend and friend whose life continues to touch, and perhaps even save, those of other young people.