The use of ancillary arterial access for complex coronary and structural heart procedures has evolved, with a shift toward radial access due to reduced vascular complications and bleeding compared to the traditional femoral approach. This chapter reviews the efficacy of ancillary radial access, particularly in transcatheter aortic valve implantation (TAVI), highlighting its advantages in minimizing major bleeding and vascular complications. In addition, ancillary radial access is proving valuable not only for TAVI but also for other structural heart procedures such as transcatheter mitral valve replacement, alcohol septal ablation, and endovascular repair of aortic coarctation. Moreover, the emergence of distal radial access (DRA) represents an alternative that has been shown to reduce vascular complications but faces technical challenges and limited device availability. Therefore, vascular access site selection remains critical to minimize complications, and DRA offers advantages in preserving radial arteries for future procedures, albeit with technical considerations.