Nobuo Sekine was one of the founding figures of Mono-ha, a major movement of the Japanese avant-garde that emerged in the late 1960s. Born in Ōmiya, Saitama Prefecture, he studied painting at Tama Art University in Tokyo, graduating in 1968. His practice quickly evolved from painting towards sculpture and installation, informed in particular by the mathematical concept of the "phase." That same year, he gained recognition with Phase-Mother Earth, a monumental work created in Kobe and now regarded as one of the seminal works of Mono-ha. Alongside Lee Ufan, Kishio Suga, and Susumu Koshimizu, Sekine developed a practice centred on the relationships between matter, space, and perception, working with materials ranging from stone, earth, and water to wood, steel, and glass. His work thus shares affinities with Minimalism, Arte Povera, Land Art, and Conceptual Art, although he was never formally affiliated with these Western movements.
His career rapidly acquired an international dimension. In 1970, he represented Japan at the 35th Venice Biennale, before exhibiting extensively throughout Europe. In the late 1970s, a major travelling solo exhibition was presented at the Kunsthalle Düsseldorf, the Louisiana Museum of Modern Art, the Kröller-Müller Museum, and the Henie Onstad Art Centre. From 1973 onwards, with the establishment of his Environmental Art Studio, Sekine also developed numerous monumental sculpture and environmental art projects. During the 1980s, his investigations continued through the Phase Conception series, works on paper combining materials such as Japanese paper, paint, graphite, and gold leaf. In these works, gold leaf becomes a sensitive surface in its own right, revealing folds, incisions, reliefs, and transformations of the support.
International interest in Sekine's work was renewed from the 2000s onwards, and his work was featured in major exhibitions at MoMA in New York, the Centre Pompidou, the Guggenheim, and MOCA Los Angeles. In 2014, Blum & Poe presented his first solo exhibition in North America at its Los Angeles gallery. His works are now held in numerous institutional collections, including the National Museum of Art, Osaka; the Hiroshima City Museum of Contemporary Art; the Hakone Open-Air Museum; the Louisiana Museum of Modern Art; the Kröller-Müller Museum; the Henie Onstad Art Centre; and the Pinault Collection in Paris. Sekine spent the final years of his life in Los Angeles, where he died in 2019, leaving behind a body of work that remains essential to the history of Mono-ha and postwar Japanese art.