Painted in 1638 during the height of Anthony van Dyck's celebrated tenure as court painter to Charles I, this commanding portrait of Margaret Lemon captures one of the most fascinating and volatile figures in the artist's personal and professional life. Lemon, who served as van Dyck's mistress and muse for several years, is rendered with an intimacy and psychological intensity rarely extended to subjects outside the royal court. The warm, luminous flesh tones and the characteristically loose, fluid brushwork that defined van Dyck's mature English period are fully evident here, with the sitter's gaze conveying both confidence and a barely suppressed restlessness that contemporary accounts of her famously tempestuous character seem to confirm. Van Dyck's treatment of costume and surface texture demonstrates his unmatched facility for translating material luxury into paint, with the drapery handled in sweeping passages that suggest movement and life rather than mere documentation. The composition draws on the grand portrait traditions of Titian and Rubens, mentors whose influence van Dyck absorbed during his Flemish and Italian years, yet the work is unmistakably English in its more restrained emotional register and atmospheric background. The result is a portrait that operates simultaneously as a record of physical likeness and as a meditation on the complex bonds between artist and subject. Held in a distinguished private New York collection and currently presented at The Frick Collection, this work represents an exceptional opportunity to acquire a securely attributed van Dyck of considerable historical and art historical significance. Works of this intimacy, connected so directly to the artist's private life and painted during the most celebrated chapter of his career, appear on the market with extraordinary rarity.