The eye movements of two college graduates were monitored in a study of flexible reading, which is defined as the ability to adjust one's rate and approach to reading according to the purpose of reading, the difficulty of the material, and one's knowledge of the subject matter. The subjects were told to read an excerpt from a tenth grade biology textbook as if it were a homework assignment. They were tested with detailed essay and multiple choice questions after reading the selection twice. The first-reading data showed that subjects slowed down for ideas that tended to be recalled, for important ideas, for ideas that contained new or unfamiliar information, and for ideas containing a high number of prepositions essential to the gist of that idea. Analyses of the changes between first and second readings showed that the difference rate was correlated with meaning unit importance ratings, the average importance of propositions in an idea, the propositions essential to the gist of an idea, and serial position. The overall pattern of correlations showed that the subjects read important ideas 51 words per minute slower and unimportant ideas 84 words per minute faster on the second reading than they did on the first reading. These data support the notion that macro and micro variations in eye movement patterns resulted from flexible reading strategies under voluntary control. (RL)