根据国际工程合同管理的实践，在参考相关文献的基础上，提出了一套变更认定的方法．变更的界定是根据合同条件的规定，审查实际所从事的工作是否是合同所反映的工作，即承包商执行的工作是否可以从合同中合理证明是承包商的合同义务的一部分．变更往往伴随费用变化，变更还有可能引起索赔． According to the practice of international engineering contract management, based on the relevant literature, a set of methods for change identification was proposed. The definition of the change is based on the provisions of the contractual conditions, to examine whether the work actually performed is the work reflected in the contract, that is, whether the work performed by the contractor can reasonably be proved as part of the contractor’s contractual obligations from the contract. Changes are often accompanied by changes in costs, and changes may also cause claims.