Romano Roth & Dietmar Wettach

Lean Enterprise
Architecture

A practical guide to value-driven enterprise architecture

Get enterprise architecture out of the ivory tower.

From USD 12.99, suggested USD 19.99. Pay what you think it is worth.

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Cover of Lean Enterprise Architecture by Romano Roth and Dietmar Wettach: a hooded figure holding a blue blade in a red circuit-diagram corridor

Nobody was ever promoted for a beautiful diagram

They were promoted for the decision it made possible.

There is a pattern to how EA practices fail. The models get more detailed, the governance gets heavier, and the people who make the real decisions stop showing up. The architecture is correct, and nobody uses it.

Lean Enterprise Architecture treats EA as a leadership discipline that connects strategy with execution and business with technology. It applies one rule throughout: start small, deliver value early, and expand only where the organization genuinely benefits.

You will learn to build capability maps, evaluate an application landscape, design a target architecture, and defend an architecture decision in front of a portfolio board. It covers the methods in daily use, TOGAF, Zachman, ArchiMate, BPMN, DMN, UML and C4, alongside governance, portfolio management, IT controlling, cloud-native platforms, FinOps and AI.

It also covers the half that decides whether an architecture survives an audit: the Three Lines of Defense applied to architecture, digital sovereignty under DORA, NIS2, GDPR and the Swiss DSG, and the four risk tiers of the EU AI Act.

The point is to move you from executing architecture decisions to shaping them.

Written for the book

From the forewords

This book presents Enterprise Architecture as a practical tool instead of a theory. It helps people understand organizations and shape digital change.
Portrait of Prof. Dr. Oliver T. Gilbert
Prof. Dr. Oliver T. Gilbert
Professor of Computer Science, HSLU
Foreword
Students will find conceptual clarity, practitioners will discover concrete methods, and leaders will gain a unifying language that bridges boardroom vision with engineering reality.
Portrait of Prof. Markus Dobbelfeld
Prof. Markus Dobbelfeld
Co-CEO, ifolor Group
Foreword

The shape of it

Thirty-two chapters in seven parts

Each chapter stands on its own, so you can read the book end to end or go straight to the topic you need.

I

EA Foundation

Establishes the conceptual foundation for enterprise architecture, covering definitions, roles, communication, lean principles, and maturity assessment.

II

Strategy & Transformation

Connects enterprise architecture to organizational change, covering transformation planning and change management.

III

Architecture Domains

Explores the six core architecture domains: business, capability, information, application landscape, data, and integration.

IV

Governance & Steering

Covers the governance mechanisms that make architecture decisions stick: compliance frameworks, portfolio management, and IT controlling.

V

Methods & Tools

Enterprise architecture does not happen in the abstract. It requires a shared language, a structured process, and the right instruments to turn strategic intent into operational reality.

VI

Technology & AI

Addresses the technology dimension of enterprise architecture, from strategy through operations and patterns, including AI fundamentals and practice.

VII

Conclusion

Synthesizes the key themes and provides forward-looking guidance for enterprise architects.

The book in numbers

32
Chapters
7
Parts
99
Diagrams
510
Pages
Romano Roth and Dietmar Wettach with CAS Enterprise Architecture students at HSLU

Lecture companion

CAS Enterprise Architecture at HSLU

The book was written as the lecture companion for the CAS Enterprise Architecture at the Lucerne University of Applied Sciences and Arts, and built to stay on your desk afterwards. 28 of the 32 chapters map to a CAS module. The remaining 4 add material the program does not cover.

15ECTS credits
6Months, part-time
RotkreuzTaught in German

Written by

Two authors, two vantage points

Romano approaches enterprise architecture from the frontier, Dietmar from the inside. Neither could have written this book alone.

Portrait of Romano Roth

Romano Roth

Group Chief AI Officer & Partner at Zühlke

Romano Roth is Group Chief AI Officer and Partner at Zühlke, with more than two decades in finance, insurance, energy, healthcare and aerospace. He lectures at HSLU and presides over DevOpsDays Zürich.

Portrait of Dietmar Wettach

Dietmar Wettach

Head of Program at HSLU, Identity & Access Management at Flughafen Zürich AG

Dietmar Wettach runs the global roles and permissions concept at Flughafen Zürich AG. As Head of Program at HSLU he co-leads the CAS Enterprise Architecture and the CAS Cloud and Platform Manager.