Classically trained and initially influenced by guitarists such as Michael Hedges and Preston Reed, Eric Roche developed a very personal guitar style which featured driving percussion and 'extended' techniques such as two-handed tapping (still quite unusual on acoustic guitar at the time when he was pioneering his style) and the use of artificial harmonics.
It's best to view this piece as three lessons in one: the first part examines the tapping as an accompaniment approach; the next section combines fretting hand tapping and percussion and picking hand slapped and tapped harmonics; and finally, there's a simpler section where you maintain a hammer-on and pull-off sequence whilst tapping out a rhythm on the upper bout of the guitar.