You can only take three books with you to a desert island, what books do you take and why?
Such a tough question! I guess I'd take The Great Gatsby, The Book Thief, and something by Dickens, maybe David Copperfield or Our Mutual Friend. Though I'm tempted to cheat and pick a Harry Potter box set for one of them…
Most of your books have the theme of love running through them - what made you choose love?
I think the underlying theme to almost every book has to do with love, whether it's romantic or not. I try to strike a balance between the love story and the family story in my books, but I'm definitely something of a romantic, so it's something I really enjoy writing… The Storm Makers is quite different to most of your books, did you enjoy writing something completely different?
I did! That's how it started, actually – as a sort of challenge to myself to do something really different. All of my other books are realistic fiction, so I'd never had to do any real world building before, and I found it really interesting. I'd love to try it again at some point. How do you come up with book titles? Do you know what your books are called when you start writing them?
Some of them are lines from the books that really stick out to me, as was the case with The Statistical Probability of Love at First Sight and This Is What Happy Looks Like. Others just sort of seem to fit the theme, like my new one, The Geography of You and Me. But either way, I almost never have a title at the beginning. Most of them come about in the 11th hour!
What books have influenced you most in life? And do you have a favourite YA book?
Growing up, I loved books that were sad and sweet and full of heart. My favorites were Bridge to Terabithia, Where the Red Fern Grows and Tuck Everlasting, and I still re-read those fairly often. Some more recent favorites are The Book Thief, The Fault in Our Stars, and Wonder. But there are so many others, too – it would be impossible to list them all!
Is there any aspect of writing you find particularly challenging?
I'm going to defer to the great Nora Ephron here, who said, "The hardest thing about writing is writing." Out of all the books you've written, do you have a favourite?
I think I'm always fondest of the book I'm working on at any given moment, since it's so immediate to me. But if I had to choose, I'd probably say The Statistical Probability of Love at First Sight – it was the one I most enjoyed writing, and I feel very lucky that it's been so well received.

Kindle or Paperback?
Paperback!

Can you sum up your new book in 10 words.
A love story that begins in a very dark elevator.

Are any of the stories you write based on real life?
A few of my books are definitely sparked by things that have happened to me in real life – a flight with a friendly stranger, a misdirected email, a blackout in New York City – but they quickly spin off into pure fiction. My life isn't nearly dramatic enough to fill more than a few pages – and I'm completely okay with that! Your covers are always really beautiful. Do you play an active role in choosing them etc?
No, I'm just really lucky! I have a wonderful cover designer at my publisher, Liz Casal, who is a complete genius, and has done an amazing job with them. In which of your stories would you want to be the protagonist?
I certainly wouldn't mind sitting next to someone like Oliver in Statistical Probability…
Which of your characters are you most like?
I think there's a little piece of me in all of them, to be honest… Do you base your characters on real people?
I really don't, for the most part, though sometimes if a friend tells a great joke, or has a funny story about their teen years, or says something particularly interesting, it has a tendency to wind up in there. I've become a shameless eavesdropper!

Do you believe in love at first sight?
I do! It's never happened to me, but I'm an optimist and a romantic at heart, so I'd like to think it's possible… Who would you date out of the characters in your books?
If they were about 15 years older, or I was about 15 years younger…then yes, absolutely! Who wouldn't want to date one of those guys, right?

How did you get your first book published? Was it an easy process?
It was a fairly straightforward process with my first book, but before that, I wrote two novels that didn't get published, so in that sense, it was a much longer road – but a great learning experience in a lot of ways, too. I don't think I would ever have written the one that finally got published without first having written those other two. Every book has really been a stepping stone to the next one…
How did your time at St Andrews and the rest of your education influence your writing, if at all?
The year I spent at St. Andrews was one of the best experiences of my life. The creative writing program was wonderful, but even more than that, just having the time and space to write in such a beautiful place was a real gift. I loved it there more than I can say.

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