Fishbowl Discussion at Conferences: How the Format Works and How to Moderate It

When the European Implementation Event met in Newcastle in June 2025, its fishbowl presenters received a short brief. Each fishbowl would have five to seven debaters and one facilitator and last no more than 60 minutes. Slides were not expected. At some point, the facilitator would place an empty chair in the circle, and anyone from the audience could take it. If that happened, someone already in the circle had to leave voluntarily.

That last rule is the whole format. A fishbowl discussion places a small group of speakers in an inner circle, surrounded by the audience in outer rings. One seat in the middle stays free, and it turns listeners into speakers. The chair is the easy part. The rules around it are what most programmes forget to write.

This guide is for the organiser who has to sell the format to a programme committee. Its chair will ask one question before approving the slot: what if nobody sits down? Our answer, and the argument of this guide, is simple. A fishbowl only beats a panel if the empty chair comes with rules: who starts, how long a guest may stay, how the room signals and how the microphone follows the seat.

What is a fishbowl discussion?

Start with the room, because the name describes it. A few people sit in the “fishbowl” and talk, while everyone else sits around them and watches, like visitors at an aquarium. The UK participation charity Involve describes the inner circle as four to eight chairs, with the remaining chairs arranged in concentric circles around it. A facilitator usually opens with a question, and three to six selected people begin the conversation.

There are two basic versions:

• Open fishbowl: one chair in the inner circle stays empty. Any audience member can take it at any time, and someone already inside then leaves voluntarily. This is the version most conferences use.
• Closed fishbowl: all inner chairs are filled. The first group talks for a set time, then leaves, and a new group from the audience takes over. The guide to interactive formats of the European Health Forum Gastein (EHFG, 2026) describes rotations that continue until everyone has had a turn.

The same guide lists variations worth knowing. In a heterogeneous fishbowl, one person per viewpoint sits inside. In a homogeneous one, people with similar views argue their case together in rounds. And with a “visitor’s chair”, an extra seat is added for guests, with a time limit or a standing signal for whoever wants in next.

Fishbowl, panel, World Café, roundtable: which format does which job?

Before you book chairs, check that a fishbowl is the right answer to your programme question. Conference programmes use these labels loosely, and each one produces something different.

A panel puts experts side by side, and our guide to the panel discussion format shows how to keep it from turning into four short keynotes. If you want everyone talking at once, the World Café method is the better tool. And if depth among a few peers matters more than the room, a roundtable discussion keeps one group together for an hour.

The fishbowl sits in the middle. A few people speak, but the room decides who they are.

When a fishbowl earns its slot

That middle position matches what organisers say they want. In Forrester’s 2026 analysis of B2B events, two thirds of organisations said they plan more workshops, roundtables and structured networking at their events (Forrester, June 2026). The same analysis notes that presentation-heavy formats are giving way to more interaction and peer exchange. For your programme, that means one slot where the audience can talk back is becoming an expectation, not a bonus.

A fishbowl works best in three situations:

• a topic on which members disagree, such as a new fee model, a regulation or a merger,
• a follow-up to a keynote, when the room has questions the speaker cannot answer alone,
• a closing session, where you want to hear what delegates took away.

Involve names its limits just as clearly. A fishbowl rarely reaches consensus, so it is a poor tool for decisions. It also depends heavily on the facilitator, who has to stop a few voices from dominating. And it is less comfortable for shy participants. So the programme committee chair gets an honest answer: the fishbowl opens a debate, and a smaller group decides later.

Where the slot sits matters too. A fishbowl after lunch can wake a room, and how it fits between keynotes, breakouts and breaks is part of planning your conference session types as one programme.

Size and set-up: chairs, circles and microphones

Once the slot is booked, the room comes next. The classic set-up is just chairs. That works in a seminar room for 40. It stops working in a hall for 300, and this is where most conference fishbowls go wrong.

For groups of 20 to 50, the circle works as described. Involve and the EU’s URBACT programme both recommend one to two hours. People in the third ring can still see and hear the inner circle without amplification.

Once the audience outgrows the 50 that Involve recommends, plan a stage fishbowl instead. Put five chairs in a shallow arc on a low stage, facing the audience, with the empty chair at the end nearest the steps. The steps matter. Picture a delegate in row 12 who wants to join: if the free chair sits behind a lectern on a stage with no visible steps, she will stay where she is. Our guide to event seating styles shows how much floor a circle or a semicircle needs compared with theatre rows.

Then follow the microphone. In a large room, every inner chair needs its own microphone, including the empty one. A guest who sits down and has to wait for a runner loses the moment. If you stream the session, ask the technical team for a camera position that shows the empty chair. Remote viewers should see when someone takes it.

The rules of the empty chair

The set-up gets people into the circle. The rules decide whether the conversation is any good once they are there. Write them before the event, give them to the facilitator and read them out at the start:

• Starting line-up: three to six people begin, briefed in advance and chosen for different views. Involve recommends three to six starters; at EIE2025 it was five to seven debaters.
• Entry signal: agree how someone shows they want in. Standing behind the empty chair is clear. A tap on the shoulder also works in some groups, but check first that your audience is comfortable with it.
• Exit rule: when the free chair is taken, someone leaves within one contribution. The facilitator may name who, starting with the person who has spoken longest.
• Time limit: the Federal Agency for Civic Education in Germany (bpb, 2010) uses a simple rule: nobody speaks longer than two minutes at a stretch. For guests on the open chair, one or two contributions is a fair limit.
• Facilitator’s veto: the facilitator may end a contribution, close the chair for a few minutes or call the next guest. Say this out loud, so that nobody takes it personally later.

The committee chair’s second question usually follows here. What if the wrong person sits down and never leaves? With an exit rule and a time limit read out at the start, the facilitator does not need to be rude. She only needs to point at the rule.

Running a 60 minute fishbowl

With the rules in place, the session follows a fixed rhythm. Here is a version for a 60 minute conference slot with five starters and one open chair.

Keeping the chair closed for the first ten minutes is a deliberate choice. It gives the room time to understand the debate before anyone joins. Open it too early and the first guest asks a question that was answered three minutes later.

How to moderate a fishbowl

The run sheet covers the clock. The facilitator covers everything else, and Involve is right that the format succeeds or fails with this person. Brief them as carefully as you would brief a keynote speaker.

Three tasks matter most. First, prepare prompt questions, as the EIE2025 brief asked its facilitators to do. When the debate slows, a new angle keeps the circle moving. Second, invite the first guest personally. Silence after “the chair is now open” can last a long minute. A facilitator who says “I saw some nodding in the third row” makes the first step smaller. That answers the committee chair’s first question too: somebody does sit down.

Third, keep the outer circle involved even if they never move. URBACT suggests a question wall with sticky notes for anyone who does not want to speak in the middle. A short live poll before the session can do the same job. The facilitator can then bring in written questions between guests. Shy delegates then still reach the circle.

At the end, a summary is better than a final round. Name what the room agreed on, what it argued about and which question is still open.

Capturing results and continuing the conversation

The circle closes after an hour, but the debate does not. Decide before the session who records it. In a case study from the International Training Centre of the International Labour Organization (ITCILO), a nominated rapporteur took notes and presented a synthesis at the end of the day; URBACT uses a flipchart that the facilitator fills during the discussion. Photograph the question wall before it is taken down.

Then make it easy to continue. After a good fishbowl, people want to talk to a guest who said something sharp from the empty chair, or to a starter they disagreed with. Schedule a break directly after the session and send a short summary within a week. If the fishbowl is part of a larger member programme, our guide to association event management shows how one session’s findings carry into the rest of the year. To learn whether delegates valued the format, add two questions from our post event survey guide.

Solution: With Converve, you can publish the fishbowl in the conference programme with a session registration and a capacity limit, useful when the circle only seats a few rings. Starters appear with speaker profiles. After the session, delegates send meeting requests within a rule-based meeting matrix that you set up, for example members with speakers or members from the same sector, and accepted meetings land in free slots in both agendas. Read more about the programme and session features and our solutions for associations.

Frequently Asked Questions

What is a fishbowl discussion?

A fishbowl discussion is a conversation format in which a small group talks in an inner circle while the audience sits around them in outer rings. In the open version, one inner chair stays empty. Any audience member can take it and join the debate, and someone already inside then leaves.

What is the difference between an open and a closed fishbowl?

In an open fishbowl, one chair stays free and people join and leave throughout the session. In a closed fishbowl, all chairs are filled, and the whole inner group is replaced by a new group after a set time (EHFG interactive formats guide, 2026).

How many people can take part in a fishbowl?

Involve recommends 20 to 50 participants, with four to eight chairs in the inner circle. Larger audiences can work if you move the circle onto a low stage, give every inner chair a microphone and keep a clear path to the empty seat.

How long should a fishbowl discussion last?

Most guides give one to two hours (Involve, URBACT). At conferences, 60 minutes is a common slot: the European Implementation Event 2025 planned each fishbowl for a maximum of 60 minutes with five to seven debaters and one facilitator.

What is the difference between a fishbowl and a panel discussion?

On a panel, the speakers are fixed and the audience only asks questions. In a fishbowl, the audience can take a seat in the conversation itself, so the group of speakers changes during the session.

Can you run a fishbowl online?

Yes. A small group keeps their cameras on as the inner circle, while everyone else watches. Participants use the raise hand function to ask for the free spot, and the facilitator brings them in and asks one inner speaker to step back.

Conclusion: write the rules before you place the chair

A fishbowl discussion can turn a passive audience into part of the conversation, but only if the empty chair comes with rules. Decide who starts, how people signal they want in, who leaves when someone joins and how long a guest may stay. Then size the room, give the free seat a microphone and brief the facilitator as carefully as a keynote. When the programme committee chair asks what happens if nobody sits down, you will have an answer, and a plan for when somebody never stands up.

If you want delegates to turn the debate into scheduled conversations afterwards, get in touch with Converve.