Leader of the group Networks and Optimization: Guido Schäfer.

In today’s society, complex systems surround us. From transport and traffic, to behavioral economics and operations management, real-world applications often demand that we identify simple, optimal solutions among a huge set of possibilities. Our research group Networks and Optimization (N&O) does fundamental research to tackle such challenging optimization problems. 

We develop algorithmic methods to solve complex optimization problems efficiently. Our research provides efficient algorithms to some of the most challenging problems, for example, in planning, scheduling and routing. To come up with the best optimization algorithms, we combine and extend techniques from different disciplines in mathematics and computer science. 

N&O covers a broad spectrum of optimization aspects. Our expertise ranges from discrete to continuous optimization and applies to centralized and decentralized settings. We focus on both problem-specific methods and universal toolkits to solve different types of optimization problems. The key in our investigations is to understand and exploit combinatorial structures, such as graphs, networks, lattices and matroids. Our research is of high scientific impact and contributes to various fields.

In several cooperations with industry partners, the algorithmic techniques that we develop in our group have proven useful to solve complex real-world problems. We are always interested in new algorithmic challenges arising in real-world applications and are open to new cooperations.


Watch our group video to get a glimpse of our activities.


Video about our collaboration with ProRail (in Dutch)




No vacancies currently.


Current events

N&O Seminar: Marek Elias (CWI)

  • 2021-06-17T13:30:00+02:00
  • 2021-06-17T14:30:00+02:00
June 17 Thursday

Start: 2021-06-17 13:30:00+02:00 End: 2021-06-17 14:30:00+02:00

Everyone is welcome to attend the on-line N&O seminar with Marek Elias. Title of his lecture: Differentially Private Release of Synthetic Graphs.

Existence or non-existence of an edge in a graph sometimes represents a sensitive information (e.g. a friendship in some social network). To allow differentially private analysis of a graph whose edges represent such sensitive information, we would like to release it in a form of so called synthetic graph which does not reveal the private information but still approximates some features of the original private graph.
In this talk, I will present an algorithm based on optimization techniques for release of a synthetic graph which approximates cut sizes of the original private graph. In the beginning, I will also provide a short introduction to Differential Privacy. This is a joint work with Michael Kapralov, Janardhan Kulkarni, and Yin Tat Lee.

Please contact Daniel Dadush for the zoom link.

Dutch Seminar on Optimization (online series) with several speakers

  • 2021-06-24T16:00:00+02:00
  • 2021-06-24T17:00:00+02:00
June 24 Thursday

Start: 2021-06-24 16:00:00+02:00 End: 2021-06-24 17:00:00+02:00

The Dutch Seminar on Optimization is an initiative to bring together researchers from the Netherlands and beyond, with topics that are centered around Optimization in a broad sense. We would like to invite all researchers, especially also PhD students, who are working on related topics to join the events. 


Speaker: Several speakers (hopefully 12-15)

Title: Lightning Talks

Lightning talks are 1 to 5 min talks meant to foster interaction in the community. This can include:

1. Introducing yourself & what you do
2. Announcing a recent result & why its cool
3. Posing an open problem / advertising a research area (or an open position)
4. Anything awesome you want to tell us about :)

If you'd like to sign up for a talk, please let us know. It is a good opportunity to give a talk to a national audience in optimization, and we still have spots left!

Our goal is to include as many people as possible, so we'll try and fit everyone.

The lecture will be given online. Please visit the website for more information and the zoom link. 



Workshop CWI-Inria International Lab

  • 2021-07-05T00:00:00+02:00
  • 2021-07-06T23:59:59+02:00
July 5 Monday

Start: 2021-07-05 00:00:00+02:00 End: 2021-07-06 23:59:59+02:00

Workshop 2021 of the CWI-Inria International Lab. The aim of this workshop is to explore possibilities for new research collaborations between CWI and Inria. The workshop will bring together researchers from Inria and CWI and feature several sessions, each of them consisting of short presentations and discussions around a selected research area.

Participation is free but registration is mandatory. You can find the details about the program and how to register at the following webpage:


Associated Members


Current projects with external funding

  • Continuous Methods in Discrete Optimization ()
  • Smart Heuristic Problem Optimization ()
  • Wiskundecluster DIAMANT ()
  • Mixed-Integer Non-Linear Optimisation Applications (MINOA)
  • Optimization for and with Machine Learning (OPTIMAL)
  • Polynomial Optimization, Efficiency through Moments and Algebra (POEMA)
  • Vóórkomen en voorkómen van incidenten op het spoor (PPS Prorail)
  • Towards a Quantitative Theory of Integer Programming (QIP)

Related partners

  • Alma Mater Studiorum-Universita di Bologna
  • Alpen-Adria-Universität Klagenfurt
  • CNR Pisa
  • CNRS
  • Dassault Systèmes B.V.
  • IBM
  • Prorail
  • Rheinische Friedrich-Wilhelmus Universitaet Bonn
  • Technische Universität Dortmund
  • Tilburg University
  • Tromsø, Norway
  • Universita degli Studi di Firenze
  • Universität Konstanz
  • University of Birmingham
  • Universiteit van Tilburg