Frank & Emily van Dalen have been missionaries with World Witness since 1986. After 12 years in Pakistan, they served as missionary trainers for 7 years before Frank became World Witness Executive Director in 2005. After 10 years in that role, the van Dalens became full-time missionaries to Lithuania in 2015. They were seconded to the Evangelical Reformed Synod of Lithuania, where they pioneered church re-planting in Kaunas. Their long-term goal is to help this historic (est. 1557) denomination return to its Reformation roots.

In 2026, the van Dalens retired from World Witness missionary status to become full-time Volunteers in Mission, continuing to support the churches in Lithuania.