Watch the Long Finger Rolls online guitar lesson by Brad Carlton from Essential Techniques
When you're changing from one chord to another, don't lift your fingers up off the strings; "drag" them to eliminate excess motion and to dampen unwanted string noise (ie open strings). Use the grooves formed in the tips of your fingers to lock into the new string groups. Another great technique is what I call "long finger rolls". This occurs when moving from an upright finger posture to a barre and vice versa.