If the design disciplines and professions can lay special claim to urban form, a much broader array of fields is concerned with urban society, the third and last section of the book. Society is shaped by the character and interaction of human institutions, customs, laws, and policies, as well as technology and natural circumstances such as geography and climate. It is the social and cultural condensate of evolving civilization-complex, dynamic, and unwieldy. Society is not simple to analyze or explain, much less to design or control. The sum of countless vectors of different magnitude pushing in different directions, it is constantly shifting its center of gravity and trajectory, often in ways and with consequences that are not easily or immediately apparent. Nonetheless, there are some more obvious changes that seem too widespread and inexorable to be ignored by the design fields. This third and final section of the book focuses on the more salient and consequential trends and issues, with an emphasis on how they impinge on the design and planning of the built environment.