Patch angioplasty is commonly performed after carotid endarterectomy. Randomized prospective trials and meta-analyses have documented improved rates of perioperative and long-term stroke prevention as well as reduced rates of restenosis for patches compared with primary closure of the arteriotomy. Although use of vein patches is considered to be the gold standard for patch closure, newer generations of synthetic and biologic materials rival outcomes associated with vein patches. Future bioengineered patches are likely to optimize patch performance, both by achieving minimal stroke risk and long-term rates of restenosis as well as by minimizing the risk of unusual complications of prosthetic patches such as infection and pseudoaneurysm formation. In addition, lessons from bioengineered patches will likely enable construction of bioengineered and tissue-engineered bypass grafts.