At 36 years of age, former quaestors could stand for election to one of the aedile positions. Of these aediles, two were plebeian and two were patrician, with the patrician aediles called Curule Aediles. The plebeian aediles were elected by the Plebeian Council and the curule aediles were either elected by the Tribal Assembly or appointed by the reigning consul. The aediles had administrative responsibilities in Rome. They had to take care of the temples (whence their title, from the Latin aedes, "temple"), organize games, and be responsible for the maintenance of the public buildings in Rome. Moreover, they took charge of Rome's water and food supplies; in their capacity as market superintendents, they served sometimes as judges in mercantile affairs.
The Aedile was the supervisor of public works; the words "edifice" and "edification" stem from the title. He oversaw the public works, temples and markets. Therefore the Aediles would have been in some cooperation with the current Censors, who had similar or related duties. Also they oversaw the organization of festivals and games (ludi), which made this a very sought after office for a career minded politician of the late republic, as it was a good means of gaining popularity by staging spectacles.
Curule Aediles were added at a later date in the 4th century BC, and their duties do not differ substantially from plebeian aediles. However, unlike plebeian aediles, curule aediles were allowed certain symbols of rank—the sella curulis or 'curule chair,' for example—and only patricians could stand for election to curule aedile. This later changed, and both Plebeians and Patricians could stand for Curule Aedileship.
The elections for Curule Aedile were at first alternated between Patricians and Plebeians, until late in the 2nd century BC, when the practice was abandoned and both classes became free to run during all years.
While part of the cursus honorum, this step was optional and not required to hold future offices. Though the office was usually held after the quaestorship and before the praetorship, there are some cases with former praetors serving as aediles.
Read more about this topic: Cursus Honorum