The purpose of this study was to examine the effect of various navigational control options within a hypermedia learning environment on the performance of students who differed in their locus of control orientations. Ninety-three college students were classified as internal or external in their locus of control orientation based on their scores on the Adult Nowicki-Strickland Locus of Control Scale (ANSIE). They were then randomly assigned to one of three treatment groups that differed in the way participants navigated through a hypermedia instructional program dealing with the human heart. In the Linear group, participants navigated through the program in a standard linear fashion. In the Branching group, participants navigated through the program with the help of a hierarchical menu structure. In the Networked group, participants had the additional option of using embedded (associative) hyperlinks. At the conclusion of the program, participants completed a posttest that assessed two types of learning. A 2 X 3 Analysis of Variance was conducted to explore the main effects for locus of control (internal and external) and navigational control (linear, branching, and networked) and any interaction effect between the two factors. The results showed no significant differences in achievement based on participants' locus of control orientation or treatment group. There was also no significant interaction observed. The results provided no support for the hypothesis that different navigation options would improve the performance of learners differing in their locus of control orientation.