Two questions decide how safe your account is, and most organizations only think about the first: who gets in, and what they can reach once they are in.
This page gathers the articles that settle those decisions. They live in the Setup Guide section of this knowledge base, and cover what to choose and why. The rest of this section covers how to do it.
An article in this knowledge base can only be filed in one section, so the Setup Guide holds them and this page links to them rather than repeating them. You will find them under For administrators, in the Setup Guide, stage 6, Manage.
The how-to articles: inviting administrators, creating and editing roles, permissions, and transferring the account owner role. Read the articles above first if you are building out a team, then come back here.