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Structure formation in liquid crystalline polymers involves processes at different length scales.The key stages are the molecular conformations which are the basis of the tendency to form a liquid crystalline phase, and the mesoscale texture of the nematic director field, involving distortion elasticity due to defects. This paper outlines computer modelling at these different length scales as well as an approach towards linking the scales by means of calculating mesoscale model parameters from the molecular modelling. The molecular modelling stage involves the calculation of torsional potentials associated with the backbone of the polymer. These energy functions are required for generating an ensemble of chains from which the persistence length can be determined. The molecular data are used to parameterize the mesoscale modelling: Frank elastic constants, rotational diffusion constant and Ericksen shape parameter are determined. On the mesoscale, a lattice model for the director field is formulated.A Monte Carlo algorithm is employed to study the annealing of the director microstructure.Shearing is added via the Ericksen equation and a dynamics model allows simulation of flow of the director field under constant shear. As an example we study the thermotropic aromatic copolyester Vectra A.