The simulation of many-body, many-particle systems has a wide range of applications in areas such as biophysics, chemistry, astrophysics, etc. It is known that the force calculation contributes 90% of the simulation time. This is mainly due to the fact that the total number of interactions in the force is O(N/sup 2/), where N is the number of particles in the system. The fast multipole algorithm proposed by Greengard and Rokhlin (1987) reduces the time complexity to O(N). In this paper, we design an efficient, parallel fast multipole algorithm in 3D. For portability, our parallel program is implemented using the Message Passing Interface. Is it possible to obtain high performance for a computationally-intensive application using a LAN of workstations? In this paper, we attempt to answer this question, which is commonly asked by those researchers who have no access to parallel computers or supercomputers.