We report a large converse magnetoelectric (CME) effect at room temperature in a multiferroic heterostructure formed from thin layers of perpendicularly magnetized Co(x)Pd(1-x) alloys deposited on a piezoelectric single-crystal of lead magnesium niobate-lead titanate PMN-PT (001). The CME results from a strain-induced reorientation of the CoPd magnetization. By varying the composition and thickness of the Co(x)Pd(1-x) film, a large converse magnetoelectric coupling constant, alpha = 8 X 10(-7) s/m, at room temperature was found for 10 nm Co(0.25)Pd(0.75). This large CME effect results from combining a highly magnetostrictive CoPd alloy with highly piezoelectric PMN-PT. (C) 2010 American Institute of Physics. [doi: 10.1063/ 1.3531648]