Lowry began her career writing about children who face major challenges. Most had to do with family. Her first novel was "A Summer to Die". It established her as an important author of young adult fiction. Her books cover many different topics, including the future, war, and humor. They are for young adults who want to read about serious issues. Lowry is a very successful author. She won the 1990 and 1994 Newbery Medal for "Number the Stars" and "The Giver". Some of her stories are based on her childhood, like her character Anastasia Krupnik in the book "Anastasia Krupnik". Some of her most famous books are "Number the Stars", "The Giver", "Gathering Blue", "Bless This Mouse", and "Messenger".