Monks and spellcasters who seek uninterrupted meditation also revere Rao. The faith of Rao has never appealed greatly to commonfolk rulers, diplomats, sages, scholars, and philosophers make up the bulk of his faithful outside of Old Ferrond, although Rao's powerful worshipers have made their deity's teachings far more influential than mere numbers would suggest. Temples of Rao also exist in Keoland, Gran March, and on the Wild Coast. The church of Rao is a significant force in Greyhawk City, though far from the most popular faith.

Worship of Rao is also heavily concentrated in Furyondy and Bissel. Rao is most popular in Veluna, where Raoism is the official state religion. The Word of Incarum, said to be written by Incarum, a deva servitor of Rao's, is regarded as the primary religious text of the faith. Though slow to act, Rao's followers act surely, carefully, and with great force. When Raoans are stirred to battle, however, their foes find them a difficult challenge: calm, implacable, and utterly convinced through the power of reason of the righteousness of their cause. Only when the foundations of law and good are threatened should they take to the battlements. Rao's priesthood urges their followers to reject strong emotion for the calm and serenity of inner peace. Sometimes this action is violent, regrettably. For those who refuse to see reason and resort to violence first, action-governed by reason and wisdom-is required to restore the peace. Rao teaches that the greatest gift is reason, which leads to discourse, which leads to peace, which leads to serenity. He is disliked by the tempestuous Joramy.

Raoan priests gently chide priests of Zilchus for their worldliness, while clerics of Zilchus claim that Raoans are too idealistic, but there is genuine affection between the two groups. Rao treats Saint Cuthbert as a younger brother as well, and he may have originally brought the saint to Oerth from another world. Allitur is said to be his younger brother. Rao is served by Zodal, lesser god of Mercy, Hope, and Benevolence. Rao is an ally of Heironeous, Pelor, Zilchus, and Saint Cuthbert, and an enemy of Iuz and Incabulos. Rao is rarely seen without his Serene Staff, an undersized shepherd's crook that he wields as a light mace. With a mere glance, he can cause any being to fall into agreeable calmness even Nerull is not immune to this. Any time an offering of peace is made, Rao grows a day younger. Rao is often depicted as an old man with bushy white hair, dark skin, slender hands, and a peaceful smile.

World serenity symbol