Following demonstrations that chimpanzees react to video images of themselves in the same way as to their mirror images (Menzel, Savage-Rumbaugh, & Lawson, 1985; Savage-Rumbaugh & Rubert, 1986), we monitored the reactions of four western lowland gorillas (Gorilla gorilla gorilla) to video images of themselves and others at the Bristol Zoo, United Kingdom. The male, Jason, and female, Delilah, were wild-born, estimated to be 26 years old, and housed together. Another male, Jeremiah, born at Bristol and aged 5 years, was housed with the wild-born female, Diana, whose estimated age was 17 years. As these gorillas were housed in glass-fronted enclosures with glass-covered pictures on the opposite wall, they all had some experience of reflections. Portable Canon or Panasonic video-recording equipment was used, along with a 52-cm Sony television monitor, the screen of which was positioned close to the glass fronts of the enclosures, enabling the gorillas to approach to within 50 cm of it. They were presented with three conditions: (1) videotapes of unfamiliar gorillas, (2) videotapes of themselves in delayed playback (recorded the previous day), and (3) live video transmissions of themselves.