A novel by Larry Niven and Jerry Pournelle about an arcology in the middle of Los Angeles. During the novel, the arcology, called Todos Santos, is embroiled in a series of conflicts with various environmental groups as well as the City of Los Angeles, causing its people to withdraw into the arcology itself, mentally as well as physically. If such an arcology were built, Niven and Pournelle ask, would it remain part of the world around it, or would it tend towards independence?
Oath of Fealty is my favorite of the Niven/Pournelle collaborations. The characters have a depth that I felt was lacking from the other novels (particularly the Mote series), and, while several interesting technological advances are proposed, from the arcology itself to implants that allow people to "think" to computers, the primary focus is more on the people than on the technology. The novel is, however, somewhat slow in the beginning, and I've known several people to bog down before getting to the more interesting parts.
Think of it as Evolution in Action