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The Conversation-Based Learning Method

Stop Guessing. Start Knowing.

Every week spent building the wrong idea is a week you can't get back. The root cause is almost always the same: decisions made on belief, not evidence. This book gives you a repeatable method — Conversation-Based Learning — to surface real customer evidence and know which idea is worth pursuing before you start building.

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How to Know Which Idea to Pursue — tentative book cover design
DraftThe Problem

The Problem

Most idea decisions are built on opinions, not evidence.

Teams invest months building products no one wants. The fix isn't more data — it's the right conversations.

01

Gut-feel decisions

Teams rely on internal opinions and HiPPOs instead of real customer evidence, leading to expensive failures.

02

Surveys miss the “why”

Quantitative data tells you what customers do, but not why they care — the insight you need to make confident decisions.

03

Building before learning

MVP-first thinking wastes months on features. Conversations cost hours and surface what matters before you write code.

DraftThe Method (CBL)

The Method

Conversation-Based Learning

CBL combines structured customer conversations with AI assistance to generate strong evidence about idea desirability and willingness to pay.

01

Prepare with precision

Define learning goals, hypotheses, and customer segments. Use AI to sharpen your conversation structure before you speak to anyone.

02

Have learning conversations

Talk to real customers in learning mode — not selling, not surveying. Uncover the ‘why’ behind their interest.

03

Analyze for evidence

Turn conversation data into evidence with AI-assisted analysis. Separate strong signals from noise.

04

Decide with confidence

Pursue, pivot, or stop — backed by real customer evidence, not opinions.

“If you don’t understand the ‘why’ behind customer interest, you’re just collecting opinions, not evidence.”
— Paris Thomas & Christian Doll
DraftWhat’s Inside (5-Act)

What’s Inside

A 5-Act journey from questions to decisions

10 chapters. One methodology. Everything you need to validate ideas through customer conversations.

Act 1 — Why

The Case for Evidence

Why understanding customers matters, why you must never stop learning, and why conversations beat building.

Act 2 — How

Preparation

Learning goals, hypotheses, customer segments, prototypes, value propositions, pricing strategies, and conversation design.

Act 3 — How

Execution

Securing conversations, team roles, dry runs with AI, managing conversation flow, and building learning communities.

Act 4 — What Now

Analysis & Decisions

Data quality levels, actionable insights, evidence auditing, and the pursue/pivot/stop framework.

Act 5 — Beyond

Scale & Stories

Scaling CBL, integrating technology, and real-world stories from practitioners who’ve done it.

DraftReviews

Reviews

What practitioners are saying

Early reviews from consultants, product leaders, and founders who shaped the methodology.

“Quote coming soon.”
— Reviewer & role TBA
“Quote coming soon.”
— Reviewer & role TBA
“Quote coming soon.”
— Reviewer & role TBA

The Authors

Built on Strategyzer. Extended with new methodology. Sharpened with AI. Written by practitioners.

Between them, Paris and Christian have spent two decades applying Strategyzer tools with product, strategy, and innovation teams around the world. This book builds on that work — a methodology for validating ideas, a sharper day-to-day practice, and AI woven in where it genuinely helps.

Paris Thomas
Paris Thomas
Limassol

15+ years of consulting on product strategy and innovation. Co-creator of the CBL method.

LinkedIn →
Christian Doll
Christian Doll
Munich

Strategy and innovation practitioner working with global product teams. Co-creator of the CBL method.

LinkedIn →

Community

100+
practitioners contributed to this book

Not just two authors.

Product managers, consultants, strategy and innovation leaders, and founders from around the world shaped this book — with stories, feedback, and experience from their own projects.

DraftWorkshops

Workshops

Go Beyond the Book

The book gives you the methodology. Workshops let your team practice it — on real projects, with AI, guided by the authors.

Limited pre-launch workshops available

Bring CBL to Your Team

A hands-on workshop tailored to your organization. Your team works on real idea projects using AI-powered CBL workflows, with live guidance from the authors.

  • Applied directly to your team’s projects
  • AI-integrated throughout
  • Online or in-person, flexible format
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Open-enrollment workshops for individual practitioners are coming soon. Sign up to be notified when dates are announced.

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