The ever increasing use of textile reinforced composite materials for structural applications makes the development of automated and computationally efficient analysis tools a must. In this paper, a micromechanical method for predicting the thermo-mechanical behaviour of textile reinforced (twodimensional woven and braided fabrics) composites is presented. The model considers the shape and type of the yarns, yarn interactions and crimp as well as the matrix distribution. This modelling scheme consists of a multilevel automated geometric decomposition of a representative volume element (unit cell) into smaller elements (block and micro cells) containing yarn and matrix parts. This way, the problem of stress analysis for the whole unit cell is split into a number of subproblems at each level of the decomposition scheme. This top to bottom decomposition is followed by a bottom to top homogenisation scheme in which internal stresses (sub-unit cell level) are linked to external ones (unit cell level). This procedure results in the calculation of the stress-strain field and the prediction of the elastic properties of the composite. To develop this method the complementary variational principle was used. A FORTRAN software programme called TEXCOMP-CEM, has been developed to automate calculation and turn the method into a practical design tool. This program computes stiffness, micro-stress fields and first cell failure. Results obtained are comparable to those obtained experimentally and from finite element modelling. Transactions on Engineering Sciences vol 21, © 1998 WIT Press, www.witpress.com, ISSN 1743-3533