Hudson Taylor's Spiritual Secret. Recommended by Derek Baker (phenomenal in reminding us of the importance of prayer in missions)
The Spiritual Disciplines Handbook: Practices that Transform Us by Adele Calhoun. Provides more than 350 ways to practice suggested spiritual disciplines.
A Praying Life seminar put on by SeeJesus. The developer of this material is Paul Miller, the author of “A Praying Life.” This seminar is available in an online format. In 2021, the Europe region hosted several 4-hour online seminars using the “A Praying Life” material.
30 Days to a Praying Life - a series of short videos on how to use prayer cards the way that Paul Miller in “A Praying Life” does. Recommended by Ken Guenther
Apps
PrayerMate app > a free app for iOS and Android designed to help you pray more faithfully and more widely. It's been a finalist in the Premier Digital Awards several times. Highly recommended by Ken Guenther.
Pray as You Go > app for daily meditation and contemplative prayer, recommended by Bethany Reedy.