I read (and repost) a lot of articles related to missions that I come across in my Twitter feed. This one by Ed Stetzer is definitely the best I've seen in a while.

Here is an excerpt from "Missions and Missional: Embracing Both for the Glory of God":

"...when we say that mission exists because worship doesn't everywhere exist, we understand that central to the mission of God is the proclamation of the good news of the gospel so that men and women everywhere might hear, respond, repent, and give glory to God...Any talk about missions that ignores the lost and hurting immediately around us is missing part of the mission itself. But any talk about being missional that does not sense an urgency to move beyond our local territory into other tribes, tongues, and nations leads us into a biblical-theological dead end.

As the recipients of amazing grace we are compelled by divine love to join Jesus on mission so that his name and his fame might be known, not only through our individual lives and local churches, but also all over the earth."

Make sure and read the rest at the original source.