A stent graft, comprising: a stent comprising: a plurality of intersecting elongated members arranged to form a plurality of cells, at least some of the plurality of cells forming a tube with a lumen running therethrough, wherein the tube comprises first and second sections (12, 14), the first section having a substantially constant first diameter, the second section having a second diameter that is larger than the first diameter, the tube comprising a transition section between the first and second sections (12, 14), the transition section having a concave curvature extending proximally from the first section toward the second section and a convex curvature extending proximally from the concave curvature to the second section, wherein the second section has a first tier of elongate cells of the plurality of elongate cells having a first shape and rounded proximal apices and a second tier of elongate cells of the plurality of cells having a second shape different from the first shape, a tube of graft material attached to a portion of the stent, wherein the first section has multiple tiers of diamond shaped cells of the plurality of cells, the multiple tiers each having a length less than each of the first and second tiers (15, 17) of elongate cells, wherein the first section exhibits a greater force of radial expansion than the second section, wherein the rounded proximal apices of the first tier extend inwardly toward a center of the stent, wherein the elongate cells of the second tier are adjacent cells of the first tier and are adjacent cells of the first section, wherein the tube of graft material has a proximal edge disposed at or adjacent the transition section. a plurality of intersecting elongated members arranged to form a plurality of cells, at least some of the plurality of cells forming a tube with a lumen running therethrough, wherein the tube comprises first and second sections (12, 14), the first section having a substantially constant first diameter, the second section having a second diameter that is larger than the first diameter, the tube comprising a transition section between the first and second sections (12, 14), the transition section having a concave curvature extending proximally from the first section toward the second section and a convex curvature extending proximally from the concave curvature to the second section, wherein the second section has a first tier of elongate cells of the plurality of elongate cells having a first shape and rounded proximal apices and a second tier of elongate cells of the plurality of cells having a second shape different from the first shape, a tube of graft material attached to a portion of the stent, wherein the first section has multiple tiers of diamond shaped cells of the plurality of cells, the multiple tiers each having a length less than each of the first and second tiers (15, 17) of elongate cells, wherein the first section exhibits a greater force of radial expansion than the second section, wherein the rounded proximal apices of the first tier extend inwardly toward a center of the stent, wherein the elongate cells of the second tier are adjacent cells of the first tier and are adjacent cells of the first section, wherein the tube of graft material has a proximal edge disposed at or adjacent the transition section.