['The appropriateness of percutaneous intervention for moderate to severe carotid in-stent restenosis (C-ISR) is unclear. We therefore sought to compare stroke/death/myocardial infarction (MI) rates between percutaneous interventions and nonoperative management for ≥50% C-ISR.', 'We performed a single-center retrospective review of consecutive patients presenting with ≥50% C-ISR to the vascular surgery service. Demographics, comorbidities, and intraoperative and postoperative variables were obtained. The degree of stenosis was verified by review of digital subtraction or computed tomography angiograms. The primary outcome was stroke/death/MI after the diagnosis of ≥50% C-ISR. χ', 'During a 13-year period, 59 patients (75 C-ISRs) presented with ≥50% C-ISRs (n\xa0= 58 male [98%]; n\xa0= 57 C-ISRs asymptomatic [76%]) with a median age of 67.5\xa0years (62.8-74.6). The initial pathologic process underlying the original stent was atherosclerosis in 33 (70%), radiation induced in 10 (21%), prior carotid endarterectomy in 4 (9%), and unknown in 28 (37%). Forty C-ISRs underwent a percutaneous intervention (19 percutaneous angioplasty only [48%]; 21 repeated stent and percutaneous angioplasty [52%]). Median follow-up for the entire cohort was 948\xa0days (283-2322) and similar between the intervention and nonintervention arms. There were no significant differences between the arms with respect to age (P\xa0= .16), medical comorbidities (P > .05), original stent type (P\xa0= .46), or clopidogrel use (P\xa0= .74). At 30\xa0days, there was one stroke and subsequent death in the intervention arm and none in the nonintervention arm. During the follow-up period, a median of 1.0 procedure was required to maintain patency. By Kaplan-Meier analysis, there were no statistically significant differences between the intervention and nonintervention arms with respect to stroke/death/MI as a composite or any of the individual components at last follow-up (P\xa0= .82). Kaplan-Meier estimated patency was not significantly superior in the intervention vs the nonintervention arm (8.0\xa0years\xa0± 1.1 vs 5.3\xa0years\xa0± 0.7; P\xa0= .14).'] Does percutaneous intervention for carotid in-stent restenosis improve outcomes compared with nonoperative management?