Greg began his studies of Chinese medicine at the Five Branches Institute, College of Traditional Chinese Medicine, graduating in 1997 with a Master's degree in TCM. He spent the following two years studying TCM in Hangzhou, Beijing, Shanghai, and Suzhou. In 1999 he returned to the US and opened Lake Street Chinese Medicine Clinic in his home town, San Francisco.

In 2004 he returned to China and in 2005 began his PhD studies at Zhejiang Chinese Medicine University in Hangzhou, graduating in 2009 with a PhD in Clinical Chinese Medicine, focusing on clinical application of Shang Han Lun. Greg is one of the few westerners to have completed a PhD in Chinese medicine in China, entirely in Chinese, and is also one of the few westerners licensed to practice Chinese medicine in China.

From 2004 to 2010 he practiced at the North American International Hospital Hangzhou, and from 2009 to now practices at Shanghai East International Medical Centre in Shanghai Pudong, and since 2011 at Body and Soul Medical Clinic in Shangha Puxi. He focuses on Chinese herbal medicine for general internal medicine, gynaecology, and paediatrics.

While he is heavily influenced by Shang Han Lun, he takes a non-dogmatic and flexible approach to herbology that incorporates ideas from a wide range of Chinese medical currents He currently lives in Shanghai with his wife and 10 year-old son.