Gosselin & de Walque is a team of enthusiastic people who have successfully advised Prime Ministers, Ministers, Presidents of political parties, and mayors; who have managed successful electoral campaigns; who have managed large-scale public projects; and who have led the Brussels public prosecutor’s office. 

We have advised CEOs of fast-growing companies, have founded a digital marketing agency in San Fransisco that helps prestigious start-ups, and have co-founded one of the first truly eco-responsible companies in Belgium. 




Junior Advisor

Guillaume de Walque









Senior Advisor






Senior Advisor

Ermeline Gosselin


Ermeline Gosselin was the Belgian PS’s spokesperson for 7 years. She led its global communications strategy during numerous electoral campaigns and government crises. She was also a key player in designing government programs at different levels of power.  

Ermeline was previously the communications director and spokesperson to various federal, regional and community Ministers.  

Chief of staff to the mayors of Mons and Soignies from 2013 to 2019, Ermeline Gosselin possesses an extensive experience in public management. 

In addition to overseeing the daily management of these 2 cities, she coordinated major public projects, such as “Mons European Capital of Culture”, which attracted more than 2 million visitors.

She holds a Master’s degree in Journalism and Communications and a Master’s degree in Political Science, and worked as a teaching assistant at the Université Libre de Bruxelles for 10 years. 

Ermeline sits on the Board of Directors of the Loterie Nationale.

In a relationship, she is the mom of two young children, who firmly ground her in the reality of daily life.

Guillaume de Walque


Guillaume de Walque was the Belgian Prime Minister’s communications director and spokesman from 2011 to 2014. As one of his closest advisors, Guillaume developed and managed all his communications strategies. He coordinated the communications strategy of the Belgian government as well. 

Guillaume was previously a senior advisor at the Institut Emile Vandervelde, the PS’s think tank. He worked as legal counsel at the Belgian Human Rights League as well.  

In 2015, Guillaume de Walque moved to San Francisco and founded a digital marketing agency that focuses on influencer marketing and works with prestigious startups. He was previously the Vice President Business Development & Communications at Clue, a leading women’s health platform.

Guillaume started his career at the corporate law firm Simpson Thacher in New York, and then co-founded Newtree, an eco-friendly chocolate business.  

Recipient of a Fulbright Scholarship, he holds a Master of Laws (LL.M.) at Columbia University (New York) and a Master’s degree at Université catholique de Louvain (Belgium). He was admitted to the New York bar in 2001.

He is fluent in English, French, Dutch and Spanish. 

Guillaume is proud of his Belgian-French-American family, is married to Arnaud, and is the happy dad of two little boys.

Jean-Marc Meilleur


Jean-Marc Meilleur was the Public Prosecutor in Brussels from 2014 to 2021. He led both and day-to-day management of this bilingual organization of more than 450 people handling nearly 300,000 cases per year. 

In this context, he managed multiple emblematic criminal cases. He also led numerous change projects that contributed not only to the modernization of the Public Prosecutor’s Office but also to the elimination of its judicial backlog. 

Jean-Marc began his career as a lawyer and then as a corporate lawyer at Total. 

He then became Deputy Public Prosecutor in Brussels and then First Deputy Public Prosecutor, while serving as Director of Communications and Spokesperson for the Prosecutor’s Office for over 10 years. 

He is a member of the Council on Ethics in Journalism.

Perfectly bilingual in French and Dutch, Jean-Marc Meilleur holds an Inter-university Certificate in Urban Security Policy Management, a Master’s Degree in Intellectual Property from KULeuven and a Law Degree from the University of Namur and UCLouvain.