Since January 2018, Dallin H. Oaks has been the President of the Quorum of the Twelve.
The Quorum of the Twelve Apostles becomes the highest leadership body and their president becomes the most senior leader of the church.
On the death of church president Joseph Smith in 1844, Brigham Young was the Quorum President, and he persuaded the majority of church members that Smith's death left him and not Sidney Rigdon, who had been Smith's first counselor in the First Presidency, as the senior leader of the church.
Smith had reportedly taught the apostles, "Where I am not, there is no First Presidency over the Twelve.
[citation needed] The original apostles of 1835 had been ranked by age, and two of them had been excommunicated and later restored to fellowship.
The president's other duties consist of presiding at and conducting weekly meetings of the quorum in the Salt Lake Temple; making decisions about the particular assignments to be made to the members of the quorum; speaking on behalf of the quorum to members of the church and the media; scheduling twice-annual conferences for each stake and district in the church; and acting as a liaison in coordinating the work of the quorum with the First Presidency, the Quorums of the Seventy, and the Presiding Bishopric.