Abstract: Described herein are flexible implantable devices or stents that can, for example, navigate tortuous vessels of the neurovasculature. The devices can also conform to the shape of tortuous vessels of the vasculature. In some embodiments, the devices can direct blood flow within a vessel away from an aneurysm or limit blood flow to the aneurysm. Methods and structures are provided for adjusting, along a length of the device, the porosity of the device while maintaining a cross-sectional dimension. In some embodiments, a distal stent cover covers the distal end of the device and reduces friction between the stent and an inner surface of a delivery device, such as a catheter.