| O | Geological Society of America Campus | Professional | |
| O | Geological Society of Hong Kong | Others | |
| O | Geological Society of London | Professional | |
| O | Geometric Modeling and Processing (2000, 2002, 2004, 2006, 2008) | Others | |
| O | Geophysical and Astrophysical Fluid Dynamics | Others | |
| O | Geotechnical Division Committee of the Hong Kong Institution of Engineers | Others | |
| O | Geotechnical Division of the Hong Kong Institution of Engineers | Professional | |
| O | Geotechnical Engineer Registration Committee Building Ordiance Ch 123 | Others | |
| O | Geotechnical Engineers Registration Committee Panel, Buildings Department, Hong Kong SAR Government | Others | |
| O | Geotechnical Engineers Registration Committee, Buildings Depart-ment, Hong Kong SAR Government | Others | |
| O | Geriatric Specialty Group, Hong Kong Physiotherapy Association | Others | |
| O | German Research Council | Others | |
| O | Gerson Lehrman Group's Council of Healthcare | Others | |
| O | Gerson Lehrman Groups's Council of Healthcare Advisors, Gerson Lehrman Group, USA | Others | |
| O | Gertrude Simon Lutheran College | Others | |
| O | Ghana Consulate | Others | |
| O | Gideon Organization | Others | |
| O | Gifted Education Project, Christian Alliance H.C. Chan Primary School | Others | |
| O | Gifted Education Section of the Education Bureau | Others | |
| O | Gifted Sections, Education Bureau, HKSAR | Others | |
