The objective of the proposed research in this thesis is to develop a universal control framework for inverter-based resources (IBRs) to support grid stability at high IBR penetration levels. As the number of IBRs, including grid-following (GFL) and grid-forming (GFM) inverters, rapidly increases, significant stability challenges emerge due to the lack of industry standards for collaborative IBR design. The current IBR integration process relies on complex modeling and simulations. They still fail to guarantee stability across normal and abnormal operating conditions, limiting the seamless integration of distributed energy resources (DERs). This research rigorously examines interactions within IBR-dominated grids and proposes control modifications to standard IBR controls to address some of these challenges. A specifications-based framework with guidelines for each control layer, organized by time-scale separation, is proposed to enhance grid stability. Future research will focus on applying this framework to IBR controllers and developing technical metrics for efficient IBR integration, offering clear guidance to inverter vendors to support stable operation at high IBR penetration levels.