Klein Sexual Orientation Grid
The Klein Sexual Orientation Grid (KSOG) developed by Fritz Klein attempts to measure sexual orientation by expanding upon the earlier Kinsey scale. Fritz Klein founded the American Institute of Bisexuality in 1998 which is continuing his work by sponsoring bisexual-inclusive sex research, educating the general public on sexuality, and promoting the bisexual community.
Source: Wikipedia — Klein Sexual Orientation Grid (CC BY-SA 4.0)