In 2005 approximately 1.6 million Christians from the United States went on a short-term mission trip. That number represents a lot of ministry, cross-cultural engagement, time, and money.
If you are involved in leading or organizing short-term mission trips, you should take a look at Effective Engagement in Short-Term Missions: Doing It Right! (Pasadena: William Carey, 2008). It is edited by Robert J. Priest, a professor of mission at Trinity Evangelical Divinity School, and is filled with 22 helpful chapters on nearly every aspect of short-term missions. There are chapters dealing with cultural issues, the relationship of short-term and long-term missions, forging healthy and humble partnerships between churches, specialized trips such as medical and business trips, legal and liability concerns, and ways to improve the impact of short-term missions on participants.
From the Introduction, by Robert Priest:
Seminarians preparing for youth ministry will someday be expected to plan, organize and lead short-term mission (STM) trips for their youth. But nothing in their seminary education (in most seminaries until now) will provide preparation for this part of their future job description. Across America there are today thousands of mission pastors in local congregations. They will be expected to plan, lead, and coordinate STM trips, to set-up congregational partnerships, to choose, screen and train STM team leaders, but while their seminary education may well have included missiology courses, it is unlikely that such courses taught them about best practices in STM.
This book represents the single most ambitious effort to date to understand and improve upon patterns of ministry in short-term missions.