Power is an elusive concept. It can be defined as the ability or right to control people, companies or industries. But power and influence can exist even when not exercised, and someone can wield power, of course, at any level within an organization, or even outside the scope of a company.

Therefore, the concept requires a lot of research and analysis to apply to the residential real estate brokerage industry, to create a meaningful list. The 2019 edition of the annual SP200 has over 600 hours invested into it to try and do that.