He is currently deputy director for Academic Affairs and Special Projects at The Phillips Collection in Washington, D.C. Ottmann received a M.A.
[citation needed] At The Phillips Collection, he has organized the exhibitions Karel Appel: A Gesture of Color; Hiroshi Sugimoto: Conceptual Forms and Mathematical Models; Angels, Demons, and Savages: Pollock, Ossorio, Dubuffet; and Per Kirkeby: Paintings and Sculpture; and oversaw the installation of the Phillips's new permanent installation, a Wax Room created by Wolfgang Laib.
Works 1970–2011; Still Points of the Turning World: SITE Santa Fe’s Sixth International Biennial; Life, Love, and Death: The Work of James Lee Byars; Wolfgang Laib: A Retrospective; and Strange Attractors: The Spectacle of Chaos.
His publications include Yves Klein by Himself: His Life and Thought, The Genius Decision: The Extraordinary and the Postmodern Condition, and The Essential Mark Rothko.
[citation needed] In 2016, Ottmann was awarded the Medal of Chevalier of the Order of Arts and Letters.