A children's-publishing veteran at Andrea Brown Literary Agency who brings editorial-level taste to fiction across the full kidlit spectrum — picture book through YA — with a particular passion for clever-structured MG, grounded fantasy, and instantly book-talkable premises.
In brief
Jennifer Mattson is closed to queries as of April 8, 2026 — confirm before doing anything else.
Their background is unusually deep: five years as a Dutton Children's Books editor plus five years as a Booklist reviewer before joining Andrea Brown, giving them both commercial and critical instincts few agents can match.
The sales record skews heavily toward picture books and MG/YA fiction; despite stated openness to nonfiction, confirmed deals are almost entirely fiction and illustrated children's books — query nonfiction only if it is genuinely exceptional.
Repeat-client relationships with Katy Loutzenhiser and Kate Hannigan signal that Mattson invests in multi-book author careers, not just debut acquisitions.
Structure and hook are the throughlines of their wishlist: across every age group and genre, Mattson gravitates toward books with a clear, clever architecture rather than looser, mood-driven narratives.
Lately
As of January 2023, Mattson signaled a deliberate push to grow the novelist side of their list, indicating picture book and illustration representation is well-stocked and fiction is the active growth area.
What Jennifer is looking for
This is Mattson's most openly prioritized category right now. They want characters with the full MG emotional range — smart but uncertain, hopeful but prone to spectacular mistakes. Structurally tight plots and a premise that can be described in one sharp sentence are key. Mysteries with the layered, puzzle-box feel of The Westing Game are especially welcome. They have also floated a specific wishlist idea: a story set inside a middle school mariachi program, suggesting strong interest in culturally specific, community-rooted settings.
Mattson responds to YA that earns its emotional weight through craft rather than pure issue-driven momentum — they specifically flag a preference for stories that are not excessively heavy or problem-focused. A crisp structural hook is just as important at the YA level as in MG. Romantic and comedic notes are clearly welcome given their client work; a high school romcom set in a historically Black vacation community like Oak Bluffs on Martha's Vineyard is one concept they have named as a dream project.
Mattson has a clear weakness for SFF that prioritizes imagination and wonder over technical world-building machinery. 'Mind-bending but not too techie' is the guiding principle — think accessible, controlled invention rather than dense lore. Grounded fantasy set in a vivid, specific place they genuinely wish they could visit (as opposed to generic secondary worlds) is a recurring theme. Supernatural thrillers with structural cleverness and a lingering sense of strangeness round out this category.
Fresh angles on historical moments are welcome when the research is genuinely immersive and the perspective is one that reframes a familiar era rather than simply inhabiting it. Character-driven emotional authenticity matters as much as period accuracy.
Mattson will always take a close look at a picture book with a truly outstanding concept. Author-illustrators submitting polished dummies are particularly encouraged — Mattson has explicitly named picture book dummies from author-artists as something they are actively hoping to find. Note: Mattson is NOT seeking picture book writers without illustration; the interest here is in author-illustrator packages or exceptional standalone concepts strong enough to stop them cold.
Mattson describes themselves as primarily a fiction agent who occasionally cannot resist an impeccably researched nonfiction project. This is a high bar — 'occasionally' and 'impeccable' should both be taken literally. Query here only if the research rigor is exceptional and the subject is unusual.
Not the right fit
On Jennifer's list
Taste fingerprint
How to query Jennifer
Check the live submission form before doing anything else; it was closed as of April 8, 2026, and no reopening window has been announced.
Lead with the structural hook. Mattson's touchstone comps (Westing Game, Scythe, The 7½ Deaths of Evelyn Hardcastle) are all books remembered for their architecture — show in the first paragraph that your book has a similarly clever spine.
Culturally specific, vividly located settings are a recurring desire. If your story is rooted in a real, particular community or place, foreground that immediately rather than burying it in backstory.
Avoid positioning your YA as primarily about a social issue or trauma arc. Mattson explicitly prefers work that is not too heavy or problem-driven — frame the plot engine and character voice first.
Author-illustrators with completed picture book dummies should say so up front; Mattson named this as an active want, and a polished dummy differentiates a submission in this crowded category.
For nonfiction, the bar is genuinely high — use the word 'impeccably researched' as a self-check. If you can't demonstrate extraordinary primary-source depth in a single sentence of your query, reconsider submitting nonfiction to Mattson.
Mattson's personal obsessions (close-up magic, supper clubs with secret entrances, rivers, The Moth Radio Hour, Anthony Trollope) hint at a taste for hidden depths, storytelling as performance, and a slightly old-fashioned sense of wonder — these aren't comps, but they are useful mood calibration.
Repeat-client relationships are a pattern here; signal in your query letter that you're thinking about a career and a body of work, not just a single book.