This document discusses how improvisation can teach lessons for design. It explores how improvisation involves using tools and frameworks, establishing roles and communication, and trading parts between collaborators. The document argues that improvisation fosters new ways of thinking and acting by developing thought patterns, practices, structures and ways to behave. It has historically been important to many artistic movements like hip hop, but has declined with the shift from tape to digital formats and the internet. However, improvisation remains important for spontaneity and the real-time web, and comes most naturally in one's mother tongue.