Parallel algorithms for numerical models used in semiconductor device simulation of nonequilibrium transport in two dimensions using Monte Carlo particle methods. Such models are currently used and computed using vector serial computers. However, by adapting Monte Carlo to parallel systems, e.g. NCUBE or Sequent could result in substantial speedup and greatly enhance the scale and sophistication of such models. The methodology here will be to employ a general algorithmic analysis based on 'grain packing', a technique developed at the Oregon State University, in order to determine the optimal parti- tioning of the problem in a multi-processor systems. The research focuses on the parallel versus sequential speedup obtained through parallelization of existing sequential algo- rithms for bulk transport in GaAs and MESFET simulation using Monte Carlo methods.