This paper aims to add two concepts to the term of Smart City, ubiquity and emergence. The first term used recently in computer science to describe the impact of Information and Communication Technology (ICT) in all areas of society, being the basis of two new research areas that currently have great interest, called the Internet of Things and smart environments. The second term, widely used by some sciences (biology, theology, etc.) to describe the behavior and dynamics that occur in the real phenomena in their areas. In this paper, we analyze their contributions to help to design cities more autonomous, with more capacities of self-management and adaptation.