Karl teaches missions and church history at Bangkok Bible Seminary, and assists with translation and editing at Kanok Bannasan (OMF Publishers Thailand), one of the few publishers of Thai Christian books. Living right next to the seminary campus in downtown Bangkok, both Karl and Sun have opportunities to invest in the lives of students, the next generation of Thai church leaders. They are also involved in a new church plant called Grace City Bangkok, and Karl does itinerant preaching at various churches in the Bangkok area and beyond.
During their previous term of missionary service (2006-2010), Karl & Sun worked alongside a Thai pastor and his church to do new church planting. Living in the town of Prabaht in Central Thailand, they sought to plant a new church in the farming community of Nong Doan, about 6 miles distant from Prabaht. Karl assisted with preaching, pastoral visitation, and evangelistic outreach. In addition to being a full-time mom, Sun enjoyed discipling some women who came to see her at home.