The giraffe of Nairobi National Park, Kenya have been studied for one year. Each animal seen has been photographed from the left side and the pattern on the neck used to recognize each individual. While the pattern may become darker with age, it does not significantly change in detail even over many years. At present 65 adult male, 72 adult female and 30 immature giraffe can be recognized. Movements of individuals are described as well as associations with other individuals. The sex ratio of the giraffe is discussed in relation to that found in the plains ungulates. The population of giraffe in the Park is considered to be particularly high and the relation of giraffe to the vegetation is discussed briefly.