Adjunct Professor, Life Sciences 
School of Life Sciences, Hebei Normal University, Shijiazhuang, China

2002-2005

Honorary Research Fellow, Acari Systematics
Department of Entomology, The Natural History Museum, London, England 

Researcher (taxonomist), Curator Acari
New Zealand Arthropod Collection, Landcare Research, Auckland, New Zealand 

Technical Officer, Senior Scientific Officer 
BioNET-INTERNATIONAL, Egham, Surrey, England 

Honorary Professor, Plant Protection 
Fujian Academy of Agricultural Sciences, Fuzhou, China 

Adjunct Professor, Life Sciences 
Fudan University, Shanghai, China 

Taxonomist, Senior Scientific Officer with tenure
CAB International Institute of Entomology (known as CABI Bioscience from 1998) in The Natural History Museum, London, England 

Taxonomist, High Scientific Officer
International Institute of Entomology  in The Natural History Museum, London, England 

Post-doctoral Research Associate, Insect Ecology 
Department of Entomology, Oregon State University, Corvallis, Oregon, USA 

Research Assistant, Integrated Pest Management, Insect Ecology and  Acarology
Department of Entomology, Cornell University, Ithaca, New York, USA