McDonald's Corporation is one of the best known global brands. Starting with 2004, McDonald's witnessed a turnaround from a business slow-down, and became very profitable again, despite a high turnover of CEOs. The company continues to be profitable despite the slow economy as compared to other fast food restaurants.
Serveral years ago, McDonald's leadership decided to continue to grow, using many new strategies, such as refurbishing locations, customizing service in each country and geographic area, enhancing R&D and product development, as well as marketing and packaging, extending service, offering healthy choices, and so on.

Many of these trends have continued to the current day

What functions of management has McDonald's leadership used, and continue to use in order to remain the most profitable fast food restaurant in the world?

Please provide details describeing the functions of management.