I see most people here consider the Great Commission as given to the church, or to all believers. I have a couple of points to make here. First, notice that it is given to the eleven, not to all the disciples. Secondly notice the commandment given, "Go ye therefore, and teach all nations, baptizing them in the name of the Father, and of the Son, and of the Holy Ghost." The same commandment to teach, or make disciples of, all nations says to baptize them. Now, if the command to go and teach is given to the church, or all believers, then the command (and thus the authority) to baptize is as well.
Or, could it be that the GC was given to the ministry, represented by the eleven here?
If that is the case, wouldn't it then make sense that the command to "go ye" meant just that - for the ministers to go and preach as the Spirit leads - rather than for the church to send ministers?