International Dark-Sky Association Headquarters: Tucson, Arizona

The International Dark-Sky Association (IDA), the leading organization combating light pollution worldwide, is headquartered in Tucson, Arizona.

Tucson is a fitting home: it enacted one of the world's first outdoor lighting ordinances (1972) to protect nearby major observatories (Kitt Peak, Mt. Lemmon, Steward). IDA's office coordinates global Dark Sky Places certification (parks, reserves, communities), advocacy, and education from there.