Watch the Barred Up online guitar lesson by Brad Carlton from Chord Studies: CAGED Chords Vol. 2
This progression is a vi - ii - iii in the key of C. For the Am we'll use our standard six string barre chord, which is derived from the Em folk chord form. Then we move to the fifth string root barre chord for Dm, which is derived from the Am folk chord form. We wrap things up with an Em chord derived from the Cm form. Watch your intonation on the last chord, it's real easy to pull the second and/or fifth string out of pitch.