1981-1989 Research Scientist, Tallinn University of Technology, Tallinn, Estonia

1989-1992 Head of Laboratory of Chemical and Environmental Engineering, Tallinn University of Technology, Tallinn, Estonia

1992-2010 Senior Research Scientist (part time 2003-06 and 2007-2010) Tallinn University of Technology, Tallinn, Estonia

1998 -1999 Associate Professor, Lappeenranta University of Technology, Lappeenranta, Finland ,/p>

2001 Research Scientist (Academy of Finland) Lappeenranta University of Technology, Lappeenranta, Finland

2000-2003 Visiting Lecturer (Water Treatment Processes, 56 h/year) Lappeenranta University of Technology, Lappeenranta, Finland

2003-2004 Research Scientist (Academy of Finland) Lappeenranta University of Technology, Lappeenranta, Finland

2004-2006 Senior Scientist (Academy of Finland, program “Russia in Flux”, project 208134 “Catalytic abatement of liquid and gaseous industrial pollutants: solving acute technogenic problems”) Lappeenranta University of Technology, Lappeenranta, Finland

2006-2008 Project Manager (Enterprise Estonia Foundation, project EU23682 “Novel technology of water treatment with pulsed dielectric barrier discharge”) Tallinn University of Technology, Tallinn, Estonia

2007-2009 Senior Scientist (Finnish Founding Agency for Technology and Innovation, TEKES, project 40418/06 and 40131/08 “The development of electric discharge application to water treatment”) Lappeenranta University of Technology, Lappeenranta, Finland

2010-2013 Associate Professor (Tutkijaopettaja) Lappeenranta University of Technology, Lappeenranta, Finland

2014 University Lecturer Lappeenranta University of Technology, Lappeenranta, Finland

2015 onwards Chair Professor South China University of Technology, PR China

2015 onwards Professor Tomsk Polytechnic University, Russia