Are your roundtable discussions or breakout sessions getting too long (or too long-winded by some participants)? Try conducting these sessions using the military briefing style.

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During roundtables, have the meeting leader do a roll call. If participants have something to add, they must do so in 15 seconds or less. If they don't, instruct them to just say "pass."

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Remove the chairs and have participants stand at attention. People are less likely to be long-winded when they're not sitting comfortably in their chairs.

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Don't serve snacks. Some participants feel they need to drag the meeting out in order to "justify" their morning coffee break.

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Put a 5-minute time limit on individual topics. Once the discussion goes over the allotted time, move on. If the topic warrants further discussion, assign someone the task of scheduling a separate meeting.

Try one of all of these and let me know how it goes!