Trusted and Renowned for Getting Software Right™ Around the Globe

SIG gives technology leaders the visibility they need to address current software problems and prevent future ones from ever happening. Drawing on proprietary methods and decades of expertise, SIG helps organizations fundamentally improve the security and performance of the enterprise applications that support every aspect of their businesses.

SIG operates a unique software evaluation laboratory governed by the Quality Management System as required by the ISO/IEC 17025 international standard for testing and calibration laboratories.

The only organisation in the world certified by TÜViT for Trusted Product Maintainability, SIG is headquartered in Amsterdam with regional offices in the Nordics, Belgium, Germany and Greece. SIG serves companies in Europe, the United States, and Asia.

SIG Management Team

Dr. Erik Oltmans


Before becoming CEO, Erik served as head of consulting, then COO of SIG. Previously, he spent five years as manager and board member at the National Library. He holds a doctorate in computer science and computational linguistics. Erik is driven to ensure “Software Quality” becomes a core tenet for technology leaders around the world.

Prof. dr. ir. Joost Visser


Joost leads R&D, including innovation in tools and services. Additionally, he serves as Professor of Large-Scale Software Systems at Radboud University Nijmegen. Joost is an in-demand speaker in international scientific and academic settings. A champion of technology leaders, Joost leads a team of innovators working on their behalf.

Maureen Blandford


Maureen joined SIG to drive the digital convergence of Product • Marketing • Sales • Success. With 20+ years in B2B complex sales & marketing, Maureen, a published author, is thrilled to be able to support the world’s progressive technology leaders on their path to digital transformation by connecting them to the intellectual prowess at SIG.

Wouter Knigge


Wouter is responsible for the management of our Consultancy services, always challenging the status quo. An engineer by training, consultant by trade, pragmatic by nature, he ensures that Sales and Delivery are both customer-centric and highly efficient.

Brigitte van der Vliet

Head of Finance

Brigitte has seen the company double in size on multiple occasions. Partnering with the Board, Brigitte drives financial rigor both domestically and abroad. She is a member of the Institute of Management Accountants, the Association of Accountants and Financial Professionals in Business.

Our Clients

Providing deep code visibility to the globe’s most progressive technology leaders.

Care Autoschade
Københavns Kommune
De Goudse Verzekeringen
Port of Rotterdam
Van Lanschot
Vhi Healthcare
Vlaamse Overheid

Join Us at SIG and Be a Part of Something Special

We’re always looking for the brightest and best to join us here at the Software Improvement Group. We offer fantastic benefits, competitive salaries and a working environment that can’t be matched.

All Vacancies
  • SIG’s work is crucially important for Waternet as we elevate our online services. This digital era demands new ways of thinking about software in terms of technology, vendors and operational issues, and SIG guides us in all three areas.
    Mario Kortman Director Digital Transformation, Waternet
  • In assessing a vendor for a critical software purchase, TÜViT told us that SIG was the only one organization certified to determine if (1) the purchase was a good foundation for future excellence (2) it was worth the investment (3) it could integrate it seamlessly into our own organisation. We wouldn’t hesitate to work with SIG again.
    Markus Hölzlein General Manager Digital Products, Weltbild GmbH
  • To ensure that we continue to deliver quality in the digital world, we use the services of SIG. The software technology we develop for our learning products needs to be of the highest standards and with the expert services of SIG we can objectively determine if we meet these standards and how we can improve.
    Arnoud Klerkx CTO and member of the Management Board, Sanoma Learning