Democracy was limited in Athens because the power of government rested in the hands of very few people, and the rest of society was excluded from it. In the fourth century B.C., out of roughly 250,000 residents in the Athens area, only about 40,000 male citizens over the age of 18 participated in government. This excluded all women, children, resident foreigners and slaves.
In 507 B.C., the Athenian Cleisthenes introduced the governmental reforms he named "demokratia." This "rule by the people" consisted of three separate institutions: the ekklesia, the boule and the dikasteria. Any of the 40,000 adult male citizens could attend the ekklesia, or assembly, held in an auditorium near the Acropolis. It assembled about 40 times a year and, by popular vote, made decisions on such issues as foreign policy, war, laws and the conduct of public officials. The boule, or council of 500, met every day and conducted the practical work of the government. For terms of one year, 50 men from each of the 10 tribes of Athens sat on the boule. The dikasteria were the popular courts, and the 500 jurors were selected by lot from among the male citizens over 30 years of age. Because there were no policemen, these jurors had absolute power in bringing criminals to trial, conducting both defense and prosecution, delivering verdicts and sentencing.
Citizenship in Athens was hereditary. Only those whose parents were both citizens were automatically granted citizenship. Otherwise, it was sometimes granted to individuals by special vote of the assembly as a reward for extraordinary service.