In 2022, Arjen van der Horst returned to the NOS headquarters in Hilversum after his stint as a foreign correspondent. He resumed his role as a senior journalist, focusing on international news and continuing to contribute to NOS's reputation for high-quality journalism.

During the COVID-19 pandemic, Arjen van der Horst provided extensive coverage of the global health crisis. His reporting focused on the impact of the pandemic on international relations and the responses of various governments, offering audiences a comprehensive view of the unfolding situation.

Arjen van der Horst published a book in 2018 that delved into the complexities of global politics. The book was well-received for its thorough analysis and engaging narrative, offering readers a deeper understanding of the geopolitical landscape and the forces shaping international relations.

In 2017, Arjen van der Horst received the prestigious De Tegel award for his investigative journalism. His work on uncovering corruption within international organizations was recognized for its depth and impact, solidifying his reputation as a leading investigative journalist in the Netherlands.

Arjen van der Horst played a key role in reporting on the Paris Climate Agreement in 2015. His coverage highlighted the global efforts to combat climate change and the political negotiations involved, bringing attention to the importance of international cooperation in addressing environmental challenges.

In 2010, Arjen van der Horst was appointed as a foreign correspondent for NOS in Washington, D.C. During his tenure, he covered significant political events, including U.S. presidential elections and international diplomatic developments, providing Dutch audiences with insightful coverage from the United States.

Arjen van der Horst began his career at NOS in 2005, where he quickly established himself as a talented reporter. His early work focused on domestic news, where he honed his skills in investigative journalism and storytelling, laying the foundation for his future career.