A method and a device for the computer-assisted generation of a construction plan for modular aircraft components on the basis of already validated partial module construction plans for the individual modules wherein at least one element is assigned to a respective partial module construction plan, and in this manner a hierarchy is defined that comprises a higher, module level and a lower, element level, with the method comprising: re-utilizing at least one of the already validated partial module construction plans; depending on user input, re-specifying at the element level one of the at least one element in one of the partial module construction plans to obtain an individualized partial module construction plan; validating, only at the module level, a combination of one of the partial module construction plans with the individualized partial module construction plan; and in the case of successful validation, composing the partial module construction plans of the combination validated in this manner, to obtain the construction plan.