The Bookseller's YA Book Prize has gone to Goodbye, Perfect by Sara Barnard in its fifth year, a novel about the impact of a teacher-student relationship published by Macmillan Children’s Books.

She was awarded the £2,000 prize in a ceremony at Hay Festival on Thursday 30th May, seeing off competition from nine other shortlisted authors, including Louise O’Neill and Juno Dawson.

Goodbye, Perfect tells the story of Eden McKinley, a teenage girl who is forced to question everything when her steady, straight-A best friend Bonnie runs away with a teacher five days before the start of their GCSEs. Sworn to secrecy and bound by loyalty, only Eden knows Bonnie’s location, and she’s forced to weigh up betraying her best friend with police questioning, suspicious parents and her own growing doubts. It is Barnard’s third novel.

Talking to The Bookseller about the inspiration behind the book, she said: “I was interested in all the stories that don't get told when there's a big scandal on a national stage—all the friends, family and wider community that aren't given a voice. So, though this story features a student running away with a teacher, that's not what the story is actually about—it's about how it affects those closest to her and the people left behind.”

Everyday Sexism founder and writer Laura Bates, who was one of this year’s judges said: "Sara Barnard's writing is an absolute triumph: this book is unputdownable and beautiful, unflinching in its exploration of important and complex topics from sexual exploitation to the foster care system. But it is also a joy to read, a tender portrayal of family and sibling relationships, of flawed and poignant female friendships and of the nuanced reality of teenage experiences and the journey to discovering who you are and what you stand for."

The annual YA Book Prize was launched by The Bookseller in 2014 to celebrate great books for teenagers and young adults from the UK and Ireland. It is run in partnership with Hay Festival.

Caroline Carpenter, The Bookseller’s web editor and chair of the YA Book Prize, said: “As the YA Book Prize celebrates its fifth anniversary, this year’s shortlist—covering a diverse range of genres and timely topics—proves that the quality of YA publishing from the UK and Ireland is stronger than ever. The judges have picked a very worthy winner in Goodbye, Perfect, which tackles a difficult issue with sensitivity and nuance and is told in Sara Barnard’s characteristically readable and relatable style.”

Julia Eccleshare, Hay Festival children's director and prize judge, said: "We are delighted to welcome the The Bookseller’s YA Book Prize shortlisted authors to Hay Festival for this award ceremony. Reflecting the range of writing for YA readers and showcasing it at its best, this event gives YA readers at Hay Festival the opportunity to hear these fabulous authors talk about their books. It is also the moment to celebrate Sara Barnard as this year’s exciting and talented winner for Goodbye, Perfect."

Explore the shortlisted writers and winner on Hay Player now.