This is a symposium which was originally the subject of a special issue of on the challenge to the metropolis. The contributors include a variety of specialists each concerned with a particular aspect of the modern city -- its physical form, its technology, its politics and economics and its social implications. They discuss the rise of the modern city -- as a product of the 19th century, its changing uses, its particular values, the facilities it should have, and the forces exerting the greatest influence toward its change. The editors point out some general expectations (which have received attention from other commentators), for example, the obvious facts that leisure will increase along with automation and that as transportation and communications increase mobility will be higher. Some contributors expect the metropolis to grow at the expense of smaller cities. All agree that the metropolitan complex as a dominant environment offers fundamental opportunities for higher incomes and a wider choice of ways of living. There are two general essays on the city in the literature of Utopia and the anti-urban attitude of the American intellectual towards the city. Of interest to those engaged in city planning and students of the subject.