Long Term Missionaries

RiverStone supports over 20 long-term missionaries in Africa, Asia, India, Australia, Europe, South America and North America.  Many of the locations in the 10/40 window cannot be shared to ensure the security of our partners.  Additionally, RiverStone partners with several local ministries within the community.

The work of our partner missionaries includes equipping over 800 leaders in Peru, running a business as a mission in Asia with over 20 ladies, a children’s home with almost 50 children in Asia, working with individuals trapped in slavery and addiction in Africa, providing housing and a safe place to learn in the Philippines, raising up a generation dedicated to prayer for the nations, evangelism in the Middle East, inner city work in Australia, and much, much more.

Below is a sampling of RiverStone’s missionary partners:

Dave and Ellen Bartlett

The Canters
(Lance + Heather + Josiah + Hayley + Channing + Eireann)







In September of 2000, we moved to the West coast of Scotland to work as missionaries with Youth With A Mission (YWAM).  Since that time we have been involved in a many different types of ministry including staffing and leading YWAM’s Discipleship Training Schools (DTS), Preaching, Teaching, Strategic Intercession, and practical service in our local community.  In 2005, we pioneered a YWAM ministry called Highlands Outreach Teams, where we take short term outreach teams up into the remote areas of the Highlands and Islands of Scotland.  This ministry has been very fruitful and has continually expanded over the past few years.  As well as continuing to lead Highlands Outreach Teams, we are also currently involved in several other ministries including Healing Rooms, Light & Life, SOZO, and a marriage course called Love After Marriage.  We also lead a Home Group, and Lance runs an after school basketball club at the village primary school.  We believe that God is preparing Scotland for another great Revival, and we feel extremely honoured to be called to work in this nation in these days.

Jacob and Tatum Green








Jacob and Tatum Green are living in Denver, Colorado serving with YWAM Denver.  They help young people discover their destiny in God and equip them to fulfill it. They provide in-depth, practical training along with the opportunity to go into all the world and accomplish the Great Commission. This is accomplished by running approximately 14 training programs each year, training around 300 young people annually. As a couple, their biggest passion is making Jesus known all over the earth.  Their tasks include directing training programs, coordinating and leading outreaches, mentoring staff members, discipling students, and leading local ministry.

Arthur and Mary Alice Ivey









Arthur and Mary Alice have been serving in Peru as missionaries with TMS Global since 2001. Arthur has a strong call to disciple youth and adults in small groups and to train the Peruvians to do the same for others. Mary Alice has a call to minister to children through Kid’s Clubs, to evangelize, and to see people set free through prayer. They also work with teams that come from the states to do evangelism, discipleship, Christian business training, and medical campaigns in different places in Peru. Their hearts’ desire is to see people set free in Christ so that they can do what He has called them to do.

Erin Johnson

Erin’s missions journey has brought her from Guatemala, to Bethany College of Missions, to Cambodia, and now to the Philippines. Erin joined Action International Ministries in 2009 to join their team in reaching out to children-in-crisis. After arriving in the Philippines, the Lord led Erin and a small Filipino team to start an outreach to street children called “Brand New Day.”

Brand New Day is an outreach and rehabilitation program for street children in Cavite, Philippines. These children and youth are living, sleeping, and working on the streets due to extreme poverty, neglect, and/or abusive family situations. Brand New Day provides educational opportunities, spiritual development, a day center, and children’s home. For more information, visit Erin’s page here.

The Kirkland Family

Clay and Deborah have been on staff at the University of Georgia Wesley Foundation for thirteen years. Discipleship, leadership development, and intercession are the three primary ways Clay and Deborah serve in Athens, GA.  Wesley, at it’s heart, is a discipleship ministry, and each week, over five hundred students are discipled through Wesley.  These students are discipled by both older students and ministry interns.  The ministry interns are discipled by associate directors.  The male associate directors are discipled by Clay, and the female associate directors are discipled by Deborah.

Clay is the director of staff development, and his primary work consists in giving leadership to the UGA Wesley Internship Program.  The program consists of recent college graduates that give 1-3 years of time to both serve in a ministry area and receive leadership development and spiritual formation.  Over the past four years, there have been over fifty interns a year who have participated.  Deborah has been a leader in the prayer movement of Wesley and the city of Athens for fifteen years.  She co-leads several all-city prayer meetings a year and is on the board of directors for the prayer room of Athens.  However,  her primary ministry occurs as she spends time in prayer on behalf of the campus and city.

The Maddock Family

Geoff and Sherry live in an underserved neighborhood in Lexington, Kentucky with their son.  From 1998 till 2010 they have worked in a leadership capacity with Communality (a missional community they helped plant and nurture in Lexington).  Since 2010 they have continued to serve as missionaries with a renewed focus on neighborhood outreach and service.  The Maddock’s spend their time practicing hospitality and visiting with neighbors on front porches, in community gardens, and living rooms.  Their wider involvement in transformation means serving terms on neighborhood associations, non-profit boards, city government committees, and local food economy initiatives.  They work part-time jobs to supplement their missionary support.  Their main support comes from friends, family, and several churches in Georgia.  Each year they host mission teams in the neighborhood as a way to meet the needs of the neighbors and give mission team members insight into race and poverty issues in their context.  They long to see God’s Kingdom come and on some days, in small ways, experience the grace and justice of the Gospel in a neighborhood beset by drugs, violence, and economic hardship.

Jeff and Kristian Price





The Prices serve at the International House of Prayer in Kansas City, MO (IHOP-KC).  As full-time intercessory missionaries their primary occupation and function is ministry to Jesus through night and day worship and prayer. They stand petitioning for the light of Jesus Christ to shine into the darkness of this world and for the gospel of Jesus to spread to the nations through and by the entire church. Foundational to their work week is 25 hours of worship and intercession. From this place of prayer, works of compassion to the poor, widows, orphans, and victims of injustice flow through 25 hours of service and outreach.

Though their primary ministry is in the place of prayer and ministering unto the Lord, their ministry does include works of justice, evangelism, and preaching the gospel. As part of IHOP-KC, the Prices assist in training over 1000 students at IHOP-KC’s Bible college, help to host approximately 100,000 visitors each year at conferences, reach out to the lost through IHOP-KC’s 28 outreach ministries,  and broadcast over 14,000 hours of prayer and worship annually in 6 languages into 215 countries around the world.

All believers are all called to love Jesus and to have a prayer life, but He is specifically calling forth intercessors whose full time occupation is to stand in the gap and minister before Him. The foundational premise as an ‘Intercessory Missionary’ is Ephesians 6:12 which tells us that “…the battle which we are fighting is not again flesh and blood (things that we can see) but against principalities and powers in the heavenly realm”. This means that the battle against injustice, darkness, and for the lost is not primarily being fought in the natural realm, but rather it is taking place in the spirit realm where angels are warring against demons and principalities. “This is why we answer God’s call to prayer. This is our primary reason and motivation in serving Him as an intercessory missionary.”

Keep up with the personal blog of the Prices: http://pricefamilyatihop-kc.blogspot.com/

Tammy Ma





Tammy Ma (H) moved to South Asia in 1998, after graduating from Asbury Theological Seminary.  She is the founder and director of K-Project.

K-Project ministers through three main avenues:

1)  K CHILDREN’S HOME:   K-Homes was founded in 1999 in a large city in South Asia. The team of three started by taking in two children whose mother had died, and father was sick with AIDS. Word spread fast, and within six months, they had virtually adopted twenty children, ages 2-10!! Their hands were full, but so were their hearts!

Over the years K-Homes has taken in other children from extreme circumstances.  The national staff of 12, 47 kids, and international volunteers make up the K-Home Family. K stands for the word ‘Grace’ in the language where Tammy and team are ministering, a country that is not very open to Christianity.  These children come from a wide variety of backgrounds. From street children to orphans to children whom have been abandoned, to children from AIDS-affected families, all find grace at K-Homes. The ministry exists to give children whom literally have no where else to go, a loving family and hope!!   K-Homes is a place where children without hope can find it. Not only will they find hope, but they will also find unconditional love, joy, peace, safety and many other blessings sometimes taken for granted.

The ultimate and absolute purpose of K- homes is to provide these children with loving care in the context of family, while consistently pointing them to the cross of Christ. Their vision is to raise up children radically committed to Jesus Christ, who, empowered by His Holy Spirit, will spread the good news and transform this region of the world!

2) FAMILY SUPPORT PROGRAM:  K- Family Support Program (FSP)  supports over 85 children from single parent families in surrounding areas.  These families come from destitute desperate backgrounds. Most of the children in this program are fatherless and live at home with their widowed mother. K-Project supports these precious families through education, medical help, parent training workshops, relationship, and more.  We’ve just now witnessed the oldest of these children graduating college! Something that no one in their extended family has never dreamed of achieving!

3) SONS & DAUGHTERS:  The third area of ministry for Tammy and team is this newest endeavor.  Tammy is the founder and director of Sons and Daughters sending agency.  Sons and Daughters exists as a vehicle to partner with and send young people from the K-Homes/FSP community who feel called into full time ministry in this region of the world (10/40 window).  Sons and Daughters trains, empowers, encourages and fully supports these ‘called ones’ so that they can fully engage with the work of reaching the lost in this region. By the end of 2013, Sons and Daughters will be supporting NINE young people from K-Homes ministering in difficult places in the 10/40 window!

Allison Tebeest








Ever since I was a little girl, I have always felt called to become a missionary, specifically to Australian children. In 2014 I went on the mission field in Townsville, Australia (a city a bit north of Brisbane) and fell in love with the people and the culture! Now, the Lord has called me on another adventure in the land down under to be on staff with YWAM Townsville for 2 years. I will be helping start a daycare/school for the missionary children on the YWAM base. This will be a relief for the missionary parents who live on the base. They will be able do what God has fully called them to do in the Townsville community while their children are still in the same facility as they are, learning about Jesus and missions work! I am excited for this journey that the Lord is taking me on for the next season of my life!

Aaron & Leah Vickroy

Aaron and Leah are missionaries to the campus at the University of Georgia in Athens, GA. They met in college while attending UGA and got married following graduation. In August of 2009 they began working at the UGA Wesley Foundation and after two years of interning, came on staff as Associate Directors. They currently serve as the Director of Discipleship and Lead (Aaron) and Director of Student Connections (Leah).

As a couple, they are passionate about seeing God’s purpose, for the campus and the city, come to Athens. They are also committed to seeing young people discover who God has created them to be and the good things He has for their life. Aaron and Leah love connecting with other and fostering the relationships they have with them.