Johanna Castillo
Writers House
Likely Open
Updated: 9/19/2025
Should You Query This Agent?
1.
Agent Information
Agent Bio
Johanna Castillo is a Senior Agent at Writers House with 20+ years in publishing, formerly Vice President & Executive Editor at Simon & Schuster and Editorial Director of Atria Español for nearly fifteen years.
She has acquired, edited, or represented more than 50 New York Times bestsellers and international bestselling authors, discovered and acquired Colleen Hoover’s #1 New York Times bestseller "It Ends with Us" and many of Hoover’s early titles, and is an industry expert in books in translation and the Latine and Spanish US market.
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2.
Submission Requirements
Fiction Requirements
Nonfiction Requirements
3.
Genres
Genres Represented
Please see Publishers Marketplate link for this agent's genres information
Genres Not Represented
None listed or not available
4.
About Writers House
Agency Profile
Writers House is an independent agency that represents authors of adult and children's books, as well as illustrators and estates. It offers in-house services for international licensing, media rights, contracts, and accounting.
Agency Links
5.
Other Agents At Writers House (28 Total)
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