Katherine Noel Valentine Brosnahan (December 24, 1962 - June 5, 2018), known professionally as Kate Spade and Kate Valentine, was an American fashion designer and businesswoman. She was the founder and former co-owner of the designer brand Kate Spade New York.
After working in the accessories department at the fashion magazine Mademoiselle, Brosnahan and her husband, Andy Spade, identified a market for quality stylish handbags, and founded Kate Spade New York in 1993. The handbags Spade designed and produced quickly found popularity, owing to their sophistication and affordability, and have been described as a symbol of New York City in the 1990s.