Kellermann conducted an in-depth investigation into corporate influence in Dutch politics. Her findings revealed significant lobbying efforts by major corporations, prompting discussions about transparency and accountability in political processes.

In 2021, Kellermann launched a podcast series focused on social justice issues. The series featured interviews with activists, policymakers, and affected individuals, providing a platform for underrepresented voices and fostering important conversations on equity and justice.

Joanne Kellermann published a book exploring the effects of climate change on urban environments. The book received critical acclaim for its thorough research and compelling narrative, contributing to the broader discourse on environmental issues in the Netherlands.

In 2017, Kellermann was awarded the prestigious De Tegel award for her investigative journalism. Her work on exposing corruption within municipal governments was recognized for its depth and impact, solidifying her reputation as a leading investigative journalist in the Netherlands.

Joanne Kellermann joined De Correspondent, a platform known for its in-depth and ad-free journalism. At De Correspondent, she continued her focus on investigative reporting, delving into topics such as climate change, social justice, and economic inequality.

In 2013, Kellermann published a groundbreaking investigative series on the housing crisis in the Netherlands. Her work highlighted systemic issues within the housing market, drawing attention to the plight of low-income families and sparking national debate.

Joanne Kellermann began her career at NRC Handelsblad, one of the leading newspapers in the Netherlands. During her tenure, she focused on investigative journalism, covering a range of topics from politics to social issues, which helped her build a solid foundation in the field.