EMP simulation has been developing steadily for almost two decades. In the case of large EMP simulators intended for illumination of complete systems with correct spatial dependence, and their sometimes threat-like characteristics including correct frequency spectrum, the state of the art is rather mature. Various possibilities have been explored consistent with what Maxwell's equations allow one to do, leading to a somewhat logical list of simulator types. Some new thrusts in EMP simulation are pointed toward small EMP simulators which in some cases could be thought of as partial EMP simulators in that they illuminate a part of the system or synthesize part of the relevant sources for an EMP test. One of the promising concepts for special applications is the PARTES concept. Relying on integral equation descriptions of the electromagnetic interaction processes, and on the field equivalence principle for the synthesis of the electromagnetic fields, one can define a set of electric and magnetic dipoles which approximately synthesize proper EMP excitation by the use of superposition which implies an assumption of linearity. By varying the amplitude and phase of the sampling dipoles one can approximate any direction of incidence and polarization for a free-space plane wave over some limited volume of space.