Mezzo-fresco is painted on nearly-dry plaster, and was defined by the sixteenth-century author Ignazio Pozzo as "firm enough not to take a thumb-print" so that the pigment only penetrates slightly into the plaster. By the end of the sixteenth century this had largely displaced the buon fresco method, and was used by painters such as Gianbattista Tiepolo or Michelangelo. This technique had, in reduced form, the advantages of a secco work.
The public art mural program administered by the Beaverton Arts Program as part of its commitment to public art. The Beaverton City Council voted in April 2008 to exempt all public art from the city’s sign code and create a public art program for display of art on public rights of way and on private building facades and other private property under the terms of easements to be granted to the city for that purpose.