Recent scientific analysis of two genre paintings by Johannes Vermeer at the National Gallery of Art in Washington (Woman Holding a Balance and A Lady Writing) has uncovered a level of freedom and spontaneity in Vermeer’s preparatory painting stages that was not previously known. Researchers built on decades of research and used a suite of new, noninvasive analytical techniques to image Vermeer’s painted sketch and underpaint—layers hidden below the paintings’ surfaces—more clearly and precisely than was previously possible. Here we analyze and interpret our findings in the context of Vermeer’s career and in relation to works by his peers, high-life Dutch genre painters of the seventeenth century. For further exploration, see “Methodology & Resources,” “Experimentation and Innovation in Vermeer’s Girl with the Red Hat,” and “Vermeer’s Studio and Girl with a Flute” in this issue.