Why is it so controversial?
Partly it is due to its size, the devotion of its followers, and its unusual interpretation of Buddhist practice.
It has proved very attractive in a fast-changing society, and become wealthy on the back of generous donations. Critics have accused it of distorting the traditional teachings of Buddhism, and taking followers away from local temples.
Wat Dhammakaya is controversial for another reason too - its alleged close links to former Prime Minister Thaksin Shinawatra and the red shirt movement which supports him.