Previously he was the Manager of Technical Services of Yukos EP, where he was in charge of the design and technical analysis of a gas plant with capacity 1.8 billion m3/yr gas . His achievements include boosting oil production 17.2% per year since 1999 using ESP and Gas Lift systems .

During his career life, Dr. Zorbalas worked as a Production Manager, a Project Manager, a Technical Manager, a Production Engineer, a Production Supervisor, and a Field Engineer . He worked for many world-class oil/gas companies such as ConocoPhillips, MOBIL E&P, Schlumberger, Wintershall, Taylor Energy and Rowan Drilling before joining Yukos .

Dr. Zorbalas' technical specialty includes Artificial Lift Systems ( Gas Lift, ESP, Rod Pumping ), Production Optimization, Well Completion, Sand Control, Well Testing, PLT Correlation, acid stimulation and completion design .