Crystal Brook is named for the stream that passes through the town. It has a population of about 2400, an annual average rainfall of 400 mm, is at an altitude of 110 m above sea level and is 200 km north of Adelaide. The town, unusually for rural South Australia, has been growing steadily over the past few decades. It serves the local farming community and has many small businesses. The Crystal Brook Show is in early August; it has been held every year for a century and a quarter.
Major railway lines pass through Crystal Brook to Adelaide, Sydney, Darwin and Perth. The railway has a triangular junction. Before the construction of Beetaloo Reservoir in 1890 a spring at Bowman Park supplied water to the town. Broadband became available in April 2005 when Telstra installed an ADSL DSLAM into the local telephone exchange.
The town falls within the boundaries of the Port Pirie Regional Council. It is in the state electorate of Frome and the federal Division of Grey. Crystal Brook has sporting facilities for hockey, tennis, golf, netball, basketball, swimming, gym, horse riding, motor-cross, football and cricket. The town colours are Red and White, with most teams known as the Roosters. The town has twice successfully staged a round of the Australian Motor-cross championships.