Bats are the primary vectors of rabies in humans in the United States. In the urban environment they generally are found within buildings where they may bite people or be attacked by cats or dogs. Given the high probability that any bat that bites a person may be rabid, antirabies prophylaxis should be administered as soon as possible after the incident. This should not be delayed pending laboratory results on the bat. Children should be taught to avoid contact with moribund bats. Cats are more likely to be involved with rabid bats than dogs, but they are less likely to be vaccinated against rabies. The occasional rabid cat in an urban community may have acquired its infection from a bat. Therefore, it is vital that communities enforce rabies vaccination for cats as well as dogs.