Development of methodology for accurate and reliable condition assessment of civil structures has become increasingly important. In particular, the finite element (FE) model updating method has been successfully used for condition assessment of bridges. However, the success of applications of the method depends on the analytical conceptualization of complex bridge structures, a well-designed and controlled modal test and an integration of analytical and experimental arts. This paper describes the sensitivity-analysis-based FE model updating method and its application to structure condition assessment with particular reference to bridges, including specific considerations for FE modeling for updating and the model updating procedure for successful condition assessment. Finally, the accuracy analysis of damage assessment by model updating was investigated through a case study. (C) 2001 Elsevier Science BY. All rights reserved.