Giving to missions is how most Christians go “unto the uttermost part of the earth" to spread the Gospel, but most go about it the wrong way.  Biblically, a church sends out its own missionaries, and the congregation gives to the elders, who distribute as necessary.  Each member does not choose which para-church organization or individual he wants to support.  While each has the right to give his donations as he chooses, it is God's way to "lay them down at the apostles' feet."