Symposia were usually held in the men's quarters of the household. Singly or in pairs, the men would recline on couches arrayed against the three walls of the room away from the door. Free boys who participated did not recline but sat. Food was served, together with wine. The latter, usually mixed with water in varying proportions, was drawn from the krater, a large jar designed to be carried by two men, and served by nude servant boys from pitchers. Entertainment was provided, and depending on the occasion could include games, songs, flute-girls, slaves performing various acts, and hired entertainments. A symposium would be overseen by a symposiarch who would decide how strong or diluted the wine for the evening would be, depending on whether serious discussions or merely sensual indulgence were in the offing. Certain formalities were observed, most important among which were the libations by means of which the gods were propitiated.
In keeping with Greek notions of self-restraint and propriety, the symposiarch would prevent matters from getting out of hand. The playwright Euboulos, in a surviving fragment of a lost play has the god Dionysos describe proper and improper drinking:
For sensible men I prepare only three kraters: one for health (which they drink first), the second for love and pleasure, and the third for sleep. After the third one is drained, wise men go home. The fourth krater is not mine any more - it belongs to bad behaviour; the fifth is for shouting; the sixth is for rudeness and insults; the seventh is for fights; the eighth is for breaking the furniture; the ninth is for depression; the tenth is for madness and unconsciousness.One of the more popular games at symposia was kottabos, in which drinkers swished the dregs of their wine in their kylixes (platter-like stemmed drinking vessels) and flung them at a target. Another feature of the symposia were skolia, drinking songs of a patriotic or bawdy nature, which were also performed in a competitive manner with one symposiast reciting the first part of a song and another expected to finish it.
What are called flute-girls today were actually prostitutes or courtesans who played the aulos, a Greek woodwind instrument most similar to an oboe, hired to play for and consort with the symposiasts while they drank and conversed. When string instruments were played, the barbiton was the traditional instrument.
Symposiasts could also compete in rhetorical contests, for which reason the term symposium has come to refer to any event where multiple speeches are made.
As with many other Greek customs, the framework of the symposium was adopted by the Romans under the name of comissatio. These revels also involved the drinking of assigned quantities of wine, and the oversight of a master of the ceremonies appointed for the occasion from among the guests.