With a dumbbell in each hand, hinge forward at the hip to bring the trunk just above horizontal. Start with a row, lifting the elbows up and out to the sides to emphasize the rear delts. Return to the bottom and perform a rear delt fly—for maximal rear delt emphasis, keep the palms facing backward in the fly as well.
 
Purpose
The bent row + rear delt fly builds the upper back and lateral and rear delts—the more the palms remain facing backward and the closer the upper arm is to perpendicular to the body, the more the rear delts are targeted.
 
Programming
Generally sets of 12-20 total reps are appropriate.