Nominal Group Technique (NGT): A Structured Way to Build Consensus in Lean Six Sigma Projects

In any Lean Six Sigma project, team collaboration is the heartbeat of success. But collaboration isn’t always easy — especially when teams are diverse, opinions are strong, and time is limited. How do you make sure every voice is heard, ideas are evaluated objectively, and decisions reflect collective wisdom rather than the loudest voice in the room?

That’s where the Nominal Group Technique (NGT) comes in — a structured, democratic approach to idea generation and prioritization that ensures balanced participation and data-driven consensus.

What Is the Nominal Group Technique?

The Nominal Group Technique (NGT) is a facilitated group decision-making tool that encourages idea sharing, discussion, and prioritization in a controlled manner. It’s particularly valuable during the Analyze or Improve phases of a DMAIC project — when teams must brainstorm solutions or identify which problems to tackle first.

NGT combines the best of individual thinking and group collaboration by following a step-by-step process that eliminates groupthink and bias.

When to Use NGT in Lean Six Sigma

NGT works best when:

• You need to generate ideas or identify key issues quickly.

• Team members come from different backgrounds or levels of authority.

• Some participants tend to dominate discussions, while others remain quiet.

• The team needs to prioritize among multiple potential causes or solutions.

The NGT Process: Step-by-Step

NGT follows a clear five-step structure that balances creativity with objectivity.

Step 1: Introduction and Explanation

The facilitator sets the stage by clearly stating the problem statement or question. Example:

“What are the most important factors contributing to delays in the loan approval process?”

Ground rules are established — everyone participates, no criticism, and all ideas are valued equally.

Step 2: Silent Idea Generation

Each participant independently writes down their ideas in silence. This step eliminates influence from dominant personalities and allows individuals to think freely.

Example ideas might include:

• “Incomplete documentation”

• “Delays in system approval”

• “Too many approval layers”

Step 3: Round-Robin Sharing of Ideas

Participants take turns sharing one idea at a time, while the facilitator records each idea on a flip chart or digital board

• No discussion or evaluation yet — just listing.

• The process continues until all ideas are shared.

This ensures equal contribution and prevents early judgment from killing creativity.

Step 4: Group Discussion for Clarification

Once all ideas are listed, the team discusses each item for clarity and understanding—not to debate or critique, but to ensure everyone understands what each idea means.

Questions like:

• “Can you clarify what you meant by this?”

• “Does this overlap with any other idea?”

This stage refines the list by combining duplicates and improving wording.

Step 5: Voting and Ranking

Each team member votes or ranks the ideas based on importance, feasibility, or impact — using scoring methods like:

• Numerical ranking (e.g., 5 = high importance, 1 = low importance)

The scores are tallied, and the highest-ranked ideas are identified as the team’s top priorities.

Example:

Idea	Total Votes
Simplify approval hierarchy	22
Standardize documentation	18
Automate data checks	16

The group then focuses its energy on developing solutions for the top items.

Why NGT Works So Well

NGT balances the creativity of brainstorming with the discipline of structured decision-making. Here’s why it’s so effective in Lean Six Sigma settings:

Benefit	Description
Equal participation	Gives team members a fair voice.
Objective prioritization	Decisions are based on votes, not hierarchy.
Efficient use of time	Keeps discussions focused and purposeful.
Reduces bias	Prevents groupthink and domination by vocal members.
Creates ownership	Teams feel heard, which boosts buy-in for implementation.

NGT in Action: A Real-World Example

A financial services team was working on a Lean Six Sigma project to reduce loan processing time. After analyzing data, they identified 15 potential causes for delays. To decide which causes to address first, they applied the Nominal Group Technique.

After silent idea generation, discussion, and voting, the top three causes identified were:

1. Lack of standardized documentation.

2. Delayed manager approvals.

3. Manual data validation errors.

These priorities shaped the Improve phase, where the team introduced e-signature workflows and automated document validation, cutting processing time by 35%.

Tips for Facilitating NGT Successfully

• Keep the problem statement clear and specific. Ambiguous questions lead to unfocused ideas.

• Use a neutral facilitator. Helps maintain balance and objectivity.

• Combine NGT with other tools. Use it after brainstorming to prioritize effectively.

• Leverage digital tools for remote teams. Platforms like Miro, Mural, or Zoom whiteboards make virtual NGT sessions seamless.

NGT is ideal after brainstorming, when teams need to narrow down and focus.

Key Takeaway

The Nominal Group Technique is one of the most powerful tools for building consensus and driving decisions in Lean Six Sigma projects. By combining structure, inclusivity, and data-driven prioritization, NGT turns group discussions into actionable outcomes — ensuring the best ideas rise to the top.

In a world where collaboration often means chaos, NGT brings clarity, balance, and direction to your improvement efforts.