This course will cover the characterization and classification of organisms that constitute the microbial world (bacteria, archaea, viruses, protozoa, algae, and fungi), with an emphasis on the structure and function of microbial communities in built or otherwise human-impacted environments. We will discuss the roles of microorganisms in the environment, in industry, and in disease, to understand how microbial processes fit into complex socio-ecological systems. New York City, a dense, coastal city, will serve as our field site and laboratory, representing a valuable model for understanding how climate change will impact urban-microbial systems. By the end of this course, we will demonstrate an understanding of the core concepts of microbial ecology, will be able to communicate fundamental microbiology concepts, and will be able to analyze, interpret and evaluate a range of scientific literature.