Well, metal atoms have the ability to lose electrons very easily. And by losing electrons, they gain a positive charge. So because they are deficient electrons, they have a positive charge. And this positive charge can be used to interact with different types of molecules found inside the active side. And so the positive charges on metal ions, as we'll see in more detail in the future lectures, they can be used to basically stabilize the transit transition states as well as the intermediate molecules that are formed within that active side. They can also be used to assist in actually forming a strong nucleophile.