This dissertation reports a study that examines the effect of gender on the creation and interpretation of visuals used in diagrams of the sunflowerseed oil extraction process;Gender has long been considered an issue worth pursuing in studies of communication behaviors. Research completed on gender and communication can be divided into two areas: (1) studies investigating performance differences between males and females and (2) studies investigating the perception of differences between males and females. This dissertation explores definitions of gender and surveys research in gender and communication in both areas. It applies this research to the use of visual elements in professional communication;The study of gender in visual communication can also be divided into performance and perception categories. Studies of performance differences in the use of visual material by males and females can be found in research in psychology, art and design, and in professional communication. This research indicates that males are better than females at many visual practices. Perception research indicates that people hold stereotypes about male and female use of visual material. These perceptions create differential training and experience for males and females. This study examines both performance and perception differences in visual communication behaviors;This study used 22 diagrams of the sunflowerseed oil extraction process created by undergraduates in a technical communications course at Iowa State University. The diagrams were given to 24 graduate student raters from six academic disciplines. The raters evaluated the diagrams for visual appeal and effectiveness. They also identified the amount of technical background and the gender of each designer. Raters were interviewed after the evaluations to determine the criteria they used for their responses;Few significant results were found in performance differences. There were gender-based differences in the number of words and number of visual items used in the diagrams, in the use of angled and rounded corners, and in the use of masculine and feminine handwriting styles. Significant perception differences included raters perceiving female diagrams as more visually appealing although no more effective than male diagrams. Also, female designers were perceived as having less technical background/knowledge than male designers.