Callen Martin
The Madeleine Milburn Literary Agency
Likely Open
Updated: 4/21/2026
Agent Information
Agent Bio
Callen joined MMA in January 2026 from Bell Lomax Moreton where he worked previously, first as an assistant and then as maternity cover for a senior agent’s list, before building a Children’s, YA and New Adult list of his own.
Research Links
Query Information
Query Format
Query Format
CustomForm
Genres Information
Genres Represented
Fiction
- Children's Fiction
- New Adult Fiction
- Young Adult - Fiction
Nonfiction
Genres Not Represented
The Madeleine Milburn Literary Agency
Described as ‘a major force in publishing’ (The Bookseller), MMA is a London-based literary agency representing authors across commercial and literary adult fiction, non-fiction and children’s.
Other Agents At The Madeleine Milburn Literary Agency (6 Total)
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