While dominant participants contribute significantly to success of a meeting, they can also overwhelm, intimidate, and exclude others. Thus, you want to control their energy without losing their support.
Approach 1: Ask others to contribute
Asking quiet participants to contribute indirectly moderates more dominant participants. Say:
"Before we continue, I want to hear from rest of group."
"This is great. And I wonder what else we could do." (Look at quiet participants when you say this.)
Approach 2: Change process
A balanced dialogue equalizes participation and sequential participation (a round robin) prevents anyone from dominating discussion.
Approach 3: Include them in process
Ask dominant participants for their support during meeting. Meet with person privately and say:
"I need your help with something. It's clear to me that you know a great deal about this issue and have many good ideas. I also want to hear what other people in meeting have to say. So, I wonder if you could hold back a little, to let others contribute."
You can also retain control by giving away minor tasks. For example, dominant participants make excellent helpers. They can distribute materials, run errands, serve as scribes, deliver messages, post chart papers, run demonstration units, operate projectors, change overhead transparencies, act as greeters, and in general perform any logistical task related to meeting.
Approach 4: Create barriers
Simply move away from more aggressive participants and make less eye contact. If you are unable to see them, you are unable to recognize them as next speaker.