This paper tries to analyze some of the presently existing problems and challenges in the field of modeling bulk crystal growth processes. Strategies will be discussed to meet and overcome these problems and challenges. The different topics will be illustrated by typical examples of bulk growth of serniconductor and optical crystals. Experimental results will be used for a comparison and validation of the numerical results in order to demonstrate the status and maturity of the models. The following topics are considered: modeling of transport phenomena and three-dimensional effects, process optimization by soft computing, modeling of defect formation and finally the speed-up of computations by using PC clusters and paralellization. (C) 2004 Elsevier B.V. All rights reserved.