The mechanism of the complex enzyme nitrogenase has long been one of the most challenging problems in bioinorganic chemistry. The complexity of the metal centers of nitrogenase has stretched the boundaries of biochemical, physical and computational tools for providing insights into its structure and chemical function. Recently, there have been several key advances in crystallography and spectroscopy that have impacted the way the nitrogenase mechanism is approached. These advances have opened new frontiers in nitrogenase research, which has started to reveal novel details about the molecular structure, substrate binding and reduction. Here, we discuss these recent advances and their implications on the future of nitrogenase research.