What are your best practices in talent segmentation for managing & developing critical roles on a global scale?

We are working to identify the best practices in structuring leadership development programs to build the right skills in our most important roles, on a global scale. What has worked well in your organizations? I am also wondering if we can get insight into how companies identify talent segments? When they are identified, is it only for L&D or does it also include career-pathing, succession, acquisition and compensation? Have you left it up to the functions to develop their own talent, or centralized LD across the organization? How do you identify development needs?