The Promise is about a young child who appears to be homeless. The young child compares themselves to adults who are described to be mean, and heard, and ugly. One evening the narrator steals from an elderly. The elderly tell the narrator that they will let go of the bag if they promise to plant. The narrator promises, not understanding until opening the bag, and seeing the acorn. The acorn symbolizes the possibilities of hope of changing perceptions. The narrator plants the acorn around places that are abandoned, which begins to change others. The story ends in somewhat of a cycle, where the narrator is robbed and asks the robber to fulfill the same promise that the narrator fulfilled.

Booklist Editors' Choice - Books for Youth - Middle Readers Category: 2014, New York Times Best Illustrated Children's Books: 2014, USBBY Outstanding International Books - Grades K-2: 2015, Recipient of the SLA's award for Outstanding Contribution to Children's Non-fiction, and winner of the 2015 Green Book Award.

Author and illustrator live in the United Kingdom.

English. Originally published in UK by Walker Books in 2013. Published in the United States by Candlewick in 2017.