Theory and research concerning sexual orientation has been restricted in its scope and influence by the lack of clear and widely accepted definitions of terms like heterosexual, bisexual, and homosexual. In an attempt to better demarcate and understand the complexities of human sexual attitudes, emotions, and behavior, the Klein Sexual Orientation Grid (KSOG) was developed and administered. The KSOG is composed of seven variables that are dimensions of sexual orientation, each of which is rated by the subject as applying to the present, past, or ideal. Analysis of the data from subjects who filled out the KSOG in Forum Magazine indicated that the instrument was a reliable and valid research tool which took into consideration the multi-variable and dynamic aspects of sexual orientation.