Study of Picasso's collaboration with Norwegian artist Carl Nesjar on a group of sculptures and wall engravings using the Betograve process for pouring and engraving concrete. This collaboration led to a series of public sculptures in Europe and the United States. Illustrates these works in their final settings as well as showing the maquettes on which they were based, the photographs signed by Picasso to document his approval, and sequential photographs of construction in progress. Includes a catalog of all the Picasco/Nesjar works in Betograve, and a second catalog of works approved by Picasso but not executed. -- AATA