A new explicit fourth-order accurate staggered finite-difference time-domain (FDTD) scheme is proposed and applied to electromagnetic wave problems. It is fourth-order accurate in both space and time, conditionally stable, and highly efficient (with respect to Yee's scheme) and still retains much of the original simplicity of Yee's scheme. Both extension to perfectly matched layers and modification to deal with dielectric interfaces and perfectly conducting boundaries of the scheme have also been presented. Numerical examples are shown to illustrate the efficiency of the method. (C) 2002 Elsevier Science B.V. All rights reserved.