Stefan is the Group Head of Human Resources at UBS AG. In 2011, he joined UBS as a member of the HR Executive Committee. He was Global Head HR Corporate Center before becoming Head HR UBS Switzerland in 2012. In October 2014, he took over the responsibility as Global Head HR for Group Control and CEO Functions in addition to his role as Head HR Switzerland. In September 2016, he became the Global Head of Talent & Recuriting, with front-to-back responsibility for all talent management, development, recruiting, junior talent, and Diversity & Inclusion activities at UBS. In January 2018, he was appointed as Group Head Human Resources.

He is also an Adjunct Professor at Nanyang Business School at Nanyang Technological University, Singapore, since 2015.

Between 2006 and 2011, Stefan was Department Head of Leadership and Communication Studies at the Swiss Military Academy at ETH Zurich. His and his team's research efforts were in leadership, HR management, management development, moral decision making, conflict management, intercultural leadership, as well as leadership ethics. He also consulted various organizations in the fields of leadership and human resource management.

Between October 2010 and September 2011 he was in Singapore as a Visiting Professor at Nanyang Business School.

From 2002 to 2006, Stefan worked for Credit Suisse in Zurich and New York. He started his career as an internal management consultant and assessment specialist. He then worked for 1.5 years in New York, first as an auditor in the Investment Banking Audit Department, then as an integration manager in a global restructuring project and project leader for the implementation of a corporate Human Capital Management Process in America and Asia.

Stefan holds a PhD in Education Psychology from the University of Fribourg (CH). He is also a Lieutenant Colonel (Militia) in the Swiss Armed Forces.