A new inverse component-mode synthesis method is proposed to enhance computational efficiency of redesign of large structural systems. A large structural system is regarded as an assemblage of substructures. In the present formulation, mechanical properties of some substructures are given and those of the other substructures are to be taken as the design variables. This problem is a hybrid inverse problem. Those design variables are determined so that the fundamental natural frequency and lowest-mode deformation component ratios would attain the target values. It is shown that inverse use of the conventional component-mode synthesis technique in the hybrid inverse problem enables one to develop an efficient computational procedure for updating the design variables in the design problem. Different from the conventional component-mode synthesis method utilized for redesign, component modes of the substructure to be designed are fixed during the redesign process. The validity and order of approximation of the proposed method are demonstrated through an example model. (C) 1998 Elsevier Science S.A. All rights reserved.