A bifurcated graft is formed from a series of individual components which are intraluminally delivered apart from one another and then assembled to form a fully supported structure. The modular system includes a base member and one or more grafts connected thereto. The base member preferably includes a portion which gradually increases in diameter. A tubular device for inserting the components of the modular system and a method employing the modular system for repairing an abdominal aortic aneurysm are also disclosed.