Diadem International was set up by Lesley-Anne Leighton in 1994, initially as a humanitarian charity providing medicine for hospitals and Bibles for Christians in the Russian Federation. It has since grown to encompass other ministries such as local church planting, a leadership discipleship school, missions practice programs and ministry with the poor.

When she first met Jesus, the Lord told Lesley-Anne that she was a rough diamond in His Hand, a honed diamond in the making. Diadem in Greek means, ‘crown’. A crown does not have just one diamond, but many diamonds. Like this crown, Diadem International is now a multi-faceted ministry.

In February 2005 Lesley-Anne founded and established Holy Given International School of Missions with the purpose of training a new generation of missionaries. Holy Given schools offer a unique venture in mission training. They are based on an integrative model of learning (involving action and reflection), which acknowledges that effective learning occurs when it is experienced incarnationally. Schools are conducted in partnership with communities and churches from various locations and traditions around the world, where students have the opportunity to live and learn together in cross-cultural settings in both poor and wealthy nations and locations.

To date, over 1000 people have been trained in schools located in the United States of America, Latin America, Africa, Asia and in the Russian Federation.