Performing monkeys, a common phenomena in Asia, occupy a unique urban niche that comprises a number of factors influencing the likelihood of cross-species transmission of pathogens. Here we present the first documented evidence of exposure to measles, rubella, and parainfluenza in a population of performing monkeys. Evidence of exposure to these endemic human respiratory viruses in the performing monkeys confirms human-to-primate transmission and suggests the possibility of primate-to-human transmission. Urban animal markets, the likely source of these performing monkeys, may represent an environment conducive to the mixing of animals and pathogens, making these monkeys a potential conduit for infectious agents passing from a variety of animals found in animal markets to humans. The potential significance of these results to human public health and the unique contexts of disease transmission associated with the urban ecology of the performance monkeys are discussed. Given the level of overseas travel, this potential threat is not confined solely to Asia.