The creation of another site on a site is a great approach. Alsop typically brings his urban space under his architecture and in this case, Gehry uses the often blank surface on the roof of these connected structures.
My own work at Calderdale College in England used the same approach.
“Facebook recently got a big blue thumbs up from the Menlo Park Planning Commission to build its sprawling Frank Gehry-designed headquarters. Along with the requisite rezoning for the design, the commission approved the project’s environmental impact report, an official statement concluding that the new development would have more positive than negative effects on the area, and a cartographical change that will create a private road in front of the property called ‘Facebook Way.”
(Via Archinect.com Feed.)