We present a model for the structure formation in nematic amorphous copolymers and simulation results for a two-dimensional (2D) implementation. The model is based on a dynamic mean-field method, which allows one to specify the polymer system on two different levels of detail. On the detailed level the nematic amorphous block copolymer molecules are represented by a wormlike chain, characterized by three profiles defining its architecture. The first profile sets the sequence of different monomer types along the chain. The second distinguishes whether individual segments do or do not contribute to the nematic order. The third profile defines how the stiffness varies along the chain. On the coarsened level the system is described in terms of density distributions representing the different monomer species and an orientation distribution for the local alignment of the nematic segments. The simulations investigate how the volume fraction of the nematic component effects the resulting mesostructure. With increasing volume fraction of the nematic block 2D equivalents of "hockey puck" micelles and smectic-C and smectic-A-like structures are found. (C) 2003 American Institute of Physics.