Coupling between nearest neighbor metal nanoparticles can lead to large shifts in plasmon resonance wavelength. Here we investigate the interaction between identical silver nanoparticles numerically using finite element analysis method. The results show that for all particle shapes and sizes, the surface plasmon resonance shifts to longer wavelengths as the interparticle distance is decreased, and the shift decays exponentially with increasing interparticle distance. The shifts become vanishingly small when the distance is more than about 1.25 times the length of the particle along the direction of polarization.