International Museums and Collections:

• Museum of Modern Art, New York
• National Museum of the U.S. Navy, Washington D.C.
• Whitney Museum of American Art, New York
• Berkeley Art Museum, University of California
• Smithsonian American Art Museum, Washington D.C.
• Stanford University Center for Visual Arts
• San Angelo Museum of Fine Arts, San Angelo, TX
• Santa Barbara Museum of Fine Art, Santa Barbara
• The Art Institute of Chicago, Illinois
• National Portrait Gallery, Washington, D.C.
• Museum moderner Kunst der Stiftung Ludwig, Wien, Österreich
• Museum Neue Galerie, Kassel, Deutschland
• Museum of the Southwest, Midland, TX, USA
• The University of Texas of the Permian Basin, Odessa, TX
• MAC Museum Art & Cars, Singen, Deutschland

Some Collectors and Commissions:

• John and Dominique De Menil
• Louis Kaufman (Violinist) and Dr. Annette Kaufman
• Marlo Thomas, actress
• William Inge, writer and scriptwriter
• Dennis Hopper, actor
• Dr. William Emboden, art critic an professor
• Felix Landau, Gallery owner
• Jack Hirschmann, poet
• John Wayne, actor - commissioned Gill to paint him
• Tony Curtis, actor -  commissioned Gill to paint him
• Hans Eichel, former Minister of finance, Germany
• Kreissparkasse Heilbronn, German bank
• FBF - Stiftung für Wissenschaft und Kunst, Schmalkalden