She was the chair of the Eastern Norway Regional Health Authority during its entire existence from 2001 to 2006, later chief executive officer of Oslo University Hospital from 2009 to 2011.

Hatlen holds a "Sivilingeniør" degree in chemistry from the Norwegian Institute of Technology in 1980 and a Master of Business Administration from INSEAD in 1991.

Among others, she was responsible for the completion of the oil platform Gullfaks C.[1] In 1996 she left Statoil, and became independent[1] with a connection to the consulting firm Kjeld Rimberg & Co.[3] During this period, she was hired as chief executive of Universitetsforlaget from 1996 to 1997 and the Henie-Onstad Art Centre from 1998 to 1999, with a specialty in turning downward facing economic trends in the institutions.

[11] She resigned in 2011 following disagreements with the board of directors (headed by Göran Stiernstedt) over long-term planning.

[12] Hatlen continued her business career as chair of Sevan Marine from 2011[13] and Entra Eiendom from 2012,[14] and President of the Organizing Committee for the 2016 Winter Youth Olympics in Lillehammer[15] as well as board member of Export Credit Norway.