Particularly interested in the definition of internal spaces, he has worked in France, Italy, Greece, Japan and the United States. In Paris and Milan he studied and observed the furniture design industry which he considers an important part of an intelligent project. In 1978 William Sawaya moved to Italy and together with Paolo Moroni established Sawaya & Moroni in 1984. The firm focuses on architecture, interior design and product design. They also specialize in the production and direction of art and design exhibitions. His work is a reference for contemporary design and European architecture. His work has been published in various design and architectural books, magazines and newspapers and his work is displayed in various museums as well as in public and private collections.