This paper reports on a new electrochemical codeposition technique for microelectromechanical systems (MEMS) actuator application. Various magnetic composite materials can be obtained by incorporating hard magnetic particles with electrodeposited magnetic (either soft or hard ferromagnetic materials) metal matrices. The incorporated magnetic particle investigated is barium ferrite (BaFe12O19), and the metal matrices are electroplated nickel, CoNiMnP, and an electroless plated nickel-phosphorus alloy. Scanning electron microscopy results show that BaFe12O19 particles can be successfully incorporated into all the investigated metal matrices. The resulting magnetic properties show that materials produced by the electrochemical codeposition technique have a high coercivity (H-c) of up to 2120 Oe and a maximum magnetic energy density, (BH)(max), of up to 8.0 KJ/m(3). This indicates that the reported technique has the potential of becoming an important technique for the deposition of hard magnetic materials for magnetic MEMS actuators. (C) 2004 The Electrochemical Society.