<p>This paper explores and defends sturdiness, that p would be false were one not to believe it (~ Bp→ ~ p), as a plausible necessary condition on knowledge. Sections one and two review previously offered modal accounts of knowledge, namely sensitivity and safety. Section three outlines sturdiness in full and section four tests sturdiness against Gettier-style cases that gave trouble to other modal accounts. Sturdiness is then defended against objections from closure and knowledge of logical truths. Finally, the paper considers whether sturdiness may deliver on intuition in skeptical scenarios. The arguments here show that, given a certain reading, sturdiness is a plausible necessary condition on knowledge and motivates further exploration of the view.</p>