rukovoditi

1. (+ instr.) to manage; to run; to be in charge of
   Ona već deset godina rukovodi tim odeljenjem. — She has been running that department for ten years.
   Ko rukovodi projektom? — Who is in charge of the project?
2. formal (rukovoditi se + instr.) to be guided by; to follow
   U radu se rukovodimo zakonom i zdravim razumom. — In our work we are guided by the law and common sense.

Takes the instrumental, not the accusative: rukovoditi firmom.