Thirty-Five — also known as Benny Hill sorting or the Tournament method — is a collaborative convergence technique that rapidly identifies the single most valued idea from a large collection through a series of paired comparisons. Named after the total number of comparisons required to find the top idea from fifteen items, it transforms the intimidating task of choosing one idea from many into a series of simple one-on-one decisions that any participant can make confidently and quickly.
What It Is
In a Thirty-Five session, all ideas to be evaluated are numbered. Each participant is given a sheet with all idea numbers listed and compares them in a predetermined sequence of pairs. For each pair, the participant writes down the number of their preferred idea. After all pairs have been compared, each participant calculates which idea 'won' the most comparisons for them. The team's individual top-choice scores are then aggregated to find the collectively most preferred idea.
How to Run It
- Number all ideas on the wall from 1 to N (the method works best with ten to fifteen ideas).
- Give each participant a comparison sheet listing all the required pairs for the chosen number of ideas.
- Participants work silently through all pairs, writing the preferred idea number for each comparison.
- Each participant identifies their personal top-scored idea.
- Aggregated scores are counted across all participants to identify the group's collective top choice.
- Debate the results briefly: does the winner feel right? Are any high-scoring runners-up worth advancing alongside the winner?
When to Use It
Thirty-Five is most effective when a team needs to converge on a single favourite concept from a rich ideation session and when conventional voting methods are producing ties or political stalemate. It is particularly valuable when the group is large enough that dot voting produces ambiguous results, or when the team wants a method with more rigour and defensibility than intuitive selection.
Tips for Success
- Ensure all participants have reviewed all ideas before beginning the comparisons — uninformed comparisons corrupt the result.
- Use the method for concepts that are genuinely comparable: applying it to ideas at radically different levels of development is unfair.
- Treat the result as a starting point for conversation, not a verdict: the paired comparison process often surfaces useful information about which dimensions of value participants are using to judge ideas.
- Document the full scoring matrix: understanding why an idea scored well or poorly is as valuable as the ranking itself.
