The Nominal Group Technique (NGT) is a structured facilitation method that enables groups to generate, discuss, and prioritise ideas or solutions with significantly less bias, social pressure, and dominant-voice influence than unstructured group discussions produce. Developed by André Delbecq and Andrew Van de Ven in the 1970s, NGT is particularly valuable for project managers who need to make consequential decisions with input from groups where power imbalances, personality differences, or political sensitivities would distort the quality of an open discussion. Understanding when and how to use NGT is a valuable addition to any facilitator’s toolkit.
When to Use the Nominal Group Technique
NGT is most valuable in specific facilitation contexts. Project managers should consider NGT when: the group includes participants with significantly different levels of seniority or organisational power; the topic is politically sensitive and participants may self-censor in open discussion; previous group discussions on the same topic have been dominated by one or two voices; you need a defensible, auditable record that all perspectives were considered equally; or you are trying to build genuine consensus rather than the appearance of consensus that social pressure creates. NGT is less appropriate for quick, low-stakes decisions, small groups with high trust and equal power, or situations where the priority is rapid convergence rather than comprehensive perspective-gathering.
The Seven-Step NGT Process
Step 1: Present the Question Clearly
The facilitator presents the focus question or problem statement clearly, in writing, to all participants simultaneously. Precision matters — an ambiguous question generates divergent responses that reflect different question interpretations rather than different knowledge or perspectives. The question should be specific, unambiguous, and focused on a single issue: “What are the three most significant risks to the project in the next quarter?” rather than “What risks are you worried about?”
Step 2: Silent Individual Idea Generation
Participants spend 5–10 minutes silently writing their responses to the question independently, without discussion or interaction. This “nominal” phase — where participants work as individuals rather than as a group — is the technique’s most distinctive and most powerful element. It eliminates production blocking (the problem in group brainstorming where only one person can speak at a time), prevents anchoring (early ideas from high-status participants influencing subsequent contributions), and reduces evaluation apprehension (the self-censorship that occurs when people fear their ideas will be judged negatively in front of peers).
Step 3: Round-Robin Recording
The facilitator goes around the group systematically, asking each participant to share one idea from their list. Ideas are recorded verbatim on a whiteboard or shared screen, without discussion, evaluation, or elaboration. The round continues until all ideas from all participants’ lists have been recorded. The round-robin format ensures that every participant contributes and prevents any single participant from dominating the recorded output.
Step 4: Clarification Discussion
Once all ideas are recorded, the group discusses them for clarification — not evaluation. The purpose of this discussion is to ensure everyone understands what each idea means, not to debate which ideas are better. The facilitator manages this boundary carefully: “Can you explain what you mean by X?” is an appropriate clarification question. “Why do you think X is important?” slides toward evaluation and should be deferred to the voting phase.
Steps 5–7: Private Voting, Aggregation, and Discussion
Each participant independently and privately ranks or rates the ideas — typically selecting their top 5 ideas and assigning scores (5 for most important, 1 for least important among their selection). Votes are aggregated by the facilitator, typically by summing scores for each idea across all voters. The results reveal the group’s collective priorities mathematically, without the social pressure of public voting. The final discussion explores whether the voting results reflect the group’s genuine priorities or whether important considerations were missed — the aggregated votes inform rather than determine the final decision.
“The Nominal Group Technique’s most important design feature is that it separates idea generation from idea evaluation — and does both of them in formats that minimise the social pressures that distort both activities in conventional group discussion.” — André Delbecq, co-creator of NGT
NGT vs Other Group Decision Methods
Understanding how NGT compares to other facilitation methods helps project managers choose the right tool for each decision context:
- NGT vs Open Discussion: Open discussion is faster but produces outcomes strongly influenced by social dynamics — dominant personalities, seniority, and first-mover anchoring. NGT produces more equitable representation of all perspectives at the cost of more structured time investment.
- NGT vs Delphi Technique: Both use structured, iterative processes to surface expert consensus. Delphi is asynchronous and anonymous — appropriate for geographically distributed experts and sensitive topics. NGT is synchronous and face-to-face (or video conference) — better for groups that need to discuss and build on ideas in real time.
- NGT vs Dot Voting: Dot voting (multi-voting) is faster and more informal than NGT but provides less documentation, less structured idea generation, and less equitable voice for less vocal participants. NGT is appropriate for higher-stakes decisions; dot voting for lower-stakes prioritisation exercises.
NGT vs Other Methods Quick Comparison
| Method | Time Required | Bias Resistance | Best For |
|---|---|---|---|
| NGT | 60–90 mins | High | Power-imbalanced groups, sensitive topics |
| Open discussion | 15–45 mins | Low | High-trust, equal-power small groups |
| Delphi | Days to weeks | Very high | Distributed experts, anonymous input needed |
| Dot voting | 15–30 mins | Medium | Quick prioritisation of known options |
Key Takeaways
- NGT separates idea generation (silent individual writing) from idea evaluation (private voting) — eliminating the social pressures that distort both activities in conventional group discussion.
- Use NGT when groups contain significant power imbalances, when topics are politically sensitive, or when you need a defensible record that all perspectives were considered equitably.
- The round-robin recording phase ensures every participant contributes and prevents any single voice from dominating the captured output.
- Private voting produces an objective, aggregated picture of the group’s collective priorities without the social pressure that public voting introduces.
- NGT is more structured and time-intensive than open discussion or dot voting — reserve it for high-stakes decisions where the additional rigour justifies the investment.
- NGT’s output should inform the final decision, not determine it — the final discussion phase allows the group to consider whether the voting results reflect genuine priorities or whether important factors were missed.
