Katharine Hamnett is a British fashion designer and brand founded by Katharine Hamnett in 1979, recognised for combining clean, tailored design with strong ethical and political messaging. The label rose to prominence in the 1980s for its oversized silhouettes and iconic slogan T-shirts that made bold statements on environmentalism, human rights and social issues, worn by figures including Princess Diana and prominent musicians. Hamnett’s work has continually championed sustainability, ethical production and responsible business practices, influencing both fashion aesthetics and industry values.