Keith's first book Creepers was published when he was 24 and was shortlisted for the Guardian Fiction Award. He has since written many books including Warehouse (also shortlisted for the Guardian Fiction Award), Malarkey (shortlisted for the Booktrust Teenage Prize) and for younger readers The Runner (winner of a Smarties Silver Medal). He has lectured in Creative Writing. He spends much of his time visiting schools to pass on his love of books and writing, as well as reviewing teenage fiction.