Steve Corbett and Brian Fikkert. When Helping Hurts: How to Alleviate Poverty Without Hurting the Poor—and Yourself. 
2nd ed. Chicago: Moody, 2012. 272 pp.
From David Platt’s foreword:
[T]his book is virtually required reading for everyone in our church who is intentionally engaging the poor here and around the world. I cannot recommend it highly enough for anyone who is passionate about spreading and showing the love of Christ to the “least of these.”
Simply put, I have never read a better book on practically serving the poor, and I pray that God will use this new edition to equip his people to accomplish His purposes in a world of urgent spiritual and physical need for the glory of His great name.
I read the first edition and found it extremely helpful on the practical side of helping the poor. However, I was not as impressed by their theological argument (part 1).
On another note, I’m surprised to see Platt reference “engaging the poor” as serving the “least of these.” Using that as a reference to the poor is an example of flawed hermeneutics and leads to flawed theology (like seeing Jesus in the face of the poor). DeYoung and Gilbert demonstrated the proper understanding of that phrase in their recent book on the mission of the church (as have several commentators on the book of Matthew). I expected more from Platt.