Vieng worked as an elementary school teacher from 1999-2004, teaching 5th and 6th grade in Rosemead, CA. While there, the Lord used him to win his co-worker to Christ, as well as to encourage several co-workers to attend church. In the 1999-2000 school year, Vieng also started a weekly prayer meeting among teachers and a weekly Bible study for his fellow 5th grade teachers.

In 2004, Vieng left teaching to help pioneer a new church in Westminster, CA for three years. During this time, Vieng got married and helped disciple his wife in evangelizing at UC Irvine and Cal State Long Beach. He helped Sally win two of her ESL adult students to Christ and began initial follow-up and encouraged them to attend church.

In 2007, Vieng and Sally moved to the Bay area primarily to bless Sally's family and to see Sally's Dad come to Christ. At this time, Vieng continues to mentor his wife to lead many of her college-age students to Christ. He is currently discipling Tim Liu, an electrical engineer and computer programmer, who, along with a few friends, co-founded a start-up company called Kloudless. Tim is currently heading up their church's marketplace ministry. Tim in turn has led his friend and CEO to Christ and is reaching out to his other co-workers along with Sally and others at their church in Berkeley.