Cover Artists
The UK and US releases of the Harry Potter books feature a variety of artists who designed designed the covers and the chapter illustrations. The US covers were all illustrated by the same artist, while the UK covers were designed by a number of different artists. It's important to understand that since the UK covers were designed by different artists, they were charged with the task of creating consistency while maintaining their own style.
US Artist
Mary GrandPre designed the cover art and chapter illustrations for every United States-released Harry Potter books. GrandPre graduated from the Minneapolis College of Art and Design and has contributed artwork to a variety of children's books. She was given an early draft of each Harry Potter book and created a variety of sketches for potential cover artwork before sending them to the editors, who had the final say in the cover art. She tried to communicate the important messages and themes she gathered from the books' scripts through a specific illustrated scene. GrandPre also created an illustration for each chapter of every book, which featured an important character, item, or scene from the chapter. Although J.K. Rowling and Mary GrandPre have met, Rowling was not consulted about the US cover art, making each cover an original interpretation by the artist.
UK Artists
The Harry Potter books released in the UK each had two different book covers: an adult edition and a children's edition. The covers children's editions were illustrated by four different artists. The Harry Potter and the Philosopher's Stone children's version cover was illustrated by Thomas Taylor (as his first commissioned work when the book was still relatively unknown), Cliff Wright illustrated the second and third books, Giles Greenfield created the cover for the Goblet of Fire, and Jason Cockcroft designed the cover art for the last three books. The adult editions featured a photograph of an object or a character. Until the fifth book, two editions of the adult versions were released, with different layouts.