Meet the team

About Us

Women’s Development Track (WDT) exists to cultivate potential in Great Commission women.

We are passionate about supporting women on the frontlines of global missions by curating intentional and relational development cohorts where women can discover their unique design, develop their skills and gifts, and sustainably deploy their best contribution for maximum kingdom impact.

Melissa Singfiel

EXECUTIVE DIRECTOR

  • Dr. Melissa Singfiel has spent the last 20+ years navigating the joys and challenges of missionary life in post-war Europe. As a coach, mentor, and seasoned ministry practitioner, she knows firsthand what it takes to build healthy, sustainable leadership. Her heart for elevating women's voices began over fifteen years ago and has grown into a lifetime of leading national and global women's ministries.

    Melissa became WDT’s second executive director in 2026. With a doctorate in Leadership and Spiritual Formation, Melissa blends rich theological depth with real-world wisdom. She is on a mission to empower next-gen global women and champion collaborative leadership between men and women so everyone is free to live out their God-given calling.

Margie Burgess

BOARD MEMBER

  • Margie Burgess has poured her heart into global missions with SIM since 2011. After a five-year stint serving at a hospital in Malawi, Margie and her husband returned to the US to champion the Health Provider Advocacy Group, supporting a network of 230+ medical missionaries worldwide. As a WDT facilitator, her ultimate goal is to see women in the mission field fully equipped and encouraged to live out their callings as disciple makers and leaders.

    “Women’s Development Track modules have powerfully impacted my life and ministry.  Each module contains excellent content that is practical, challenging and renewing. . . After each WDT experience, I return home passionate about WDT as a resource for myself and my fellow workers.”

Wendy Wilson

FOUNDER & MINISTER EMERITUS

  • For over 40 years, Wendy has been a trailblazer in the missions world, dedicated to a singular, beautiful mission: helping women fully unlock their God-given design and claim their space in the Great Commission. Armed with business acumen from Texas A&M and deep theological roots from Dallas Theological Seminary, Wendy’s global journey has spanned decades of crossing cultural boundaries to mentor and coach next-gen leaders.

    After pioneering shepherding tracks for missionary women and serving as a trusted network advisor to Missio Nexus from 2012–2024, she founded the Women’s Development Track (WDT) to make collaborative growth a reality. Now retired, Wendy remains active in ministry serving as an ambassador for WDT.

Julie Grunzweig

BOARD MEMBER

  • Julie Grunzweig is a CPA who uses her financial expertise to empower purpose-driven organizations. Based in Idaho, Julie balances a professional accounting and tax practice with a deep commitment to the non-profit world. For years, she has served on the board of an educational ministry, translating complex regulatory and financial requirements into clear, actionable guidance. She has also served on the leadership team for a local women's ministry training program and regularly facilitates learning environments at her local church. As someone whose life was impacted by WDT, Julie is well-equipped to bring her whole, authentic self to the spaces where God calls her.

    It is from that experience that I am passionate about WDT opportunities to encourage and equip women to grow in their giftings and confidence in a variety of roles and seasons of life.”

Heather Althoff

BOARD MEMBER

  • Heather Althoff is the Missions Pastor at LifeWay Church in Federal Way, WA, where she helps people connect their faith to global impact. Her 22-year ministry journey spans everything from community building and small groups to youth and sports ministry overseas.

    Armed with a Bachelor’s in Classical Greek and a Master’s of Theology from Dallas Theological Seminary, Heather pairs deep theological roots with real-world experience. She’s fiercely passionate about discipleship and vocal about a major challenge: helping churches fully embrace the diverse, powerful gifts that women bring to the table. When she’s not advocating for healthy, inclusive faith communities, you can find her exploring the Pacific Northwest with her husband, Matt, and their two kids.

Wanda Walborn

BOARD MEMBER

  • Dr. Wanda Walborn spent over two decades shaping the next generation of faith leaders at Alliance University and Alliance Theological Seminary, serving as the Director of Spiritual Formation and as an institutional professor at both the Nyack and Manhattan campuses.

    Deeply passionate about launching women into leadership, she founded Empower—a unique certificate program designed to equip women in theology, mentoring, and spiritual growth. Wanda is also the author of Spiritual Journey: Can I Really Get Close to God?, a practical guide for anyone looking to deepen their faith. When she isn’t mentoring emerging leaders, she’s likely outside exploring, diving into a great book, hanging with her family, or tracking down the perfect cup of coffee.