Pope Francis named Archbishop Yeom to the College of Cardinals on Saturday, 22 February 2014. As Cardinal-Priest, he was assigned the titular church of San Crisogono. Yeom is the Third Korean national to be made Cardinal in the Catholic Church, following the two preceding Cardinal Emeritus Nicholas Cheong Jin-Suk, and the late Cardinal Stephen Kim Sou-hwan. On 23 February, the day after the announcement was made, a celebratory ceremony was held at Seoul's Myeongdong Cathedral, where he said, "I will make efforts to realize Pope Francis' vision of a Church toiling for the poor and those on the margins of society and to make it a Church serving the community. ... I respect efforts made by late Cardinal Kim and Cardinal Cheong, and will add mine to them." His appointment as cardinal was welcomed by many Koreans, though only 11 percent of the country is Catholic. On 22 May 2014, he was named member of the Congregations for the Evangelization of Peoples and for the Clergy. On Saturday, 4 October 2014, he took possession of the title of San Crisogono. He participated in Third Extraordinary General Assembly of the Synod of Bishops, Vatican City, 5 to 19 October 2014, on the theme "The Pastoral Challenges of the Family in the Context of Evangelization", by papal appointment.