This article reviews 55 experiments on the effects of text illustrations on learning. The authors examine how illustrations can aid learning of text material, focusing on the effects of normal representational pictures on the learning of information in written text. They also consider related research on nonrepresentational pictures, graphic organizers, learner-produced drawings, and mental imagery, as well as other prose learning situations. The review offers guidelines for practice. The study focuses on the effect of illustrations on learning verbal information in written text, limiting the analysis to meaningful, connected discourse, experimenter-provided illustrations, and comparisons between illustrated text and text alone. The research includes a variety of text materials, illustrations, learner differences, and dependent measures. The authors take an information-analysis approach, noting that text and illustrations may contain overlapping information (illustrated text information), information only in the text (nonillustrated text information), and information only in the pictures (picture-only information). Understanding which type of information is tested is crucial for interpreting the effects of text illustrations. Willows (1979) studied reading comprehension of children's stories with and without pictures. An example of a page from the illustrated text is shown. Some text information is also portrayed in the picture. Although the information overlap is not perfect, the authors suggest a "functional equivalence" between the picture and the text. After reading, children were asked multiple-choice questions to measure the learning of illustrated text information and nonillustrated text information. The results showed that illustrations can enhance learning of text information.This article reviews 55 experiments on the effects of text illustrations on learning. The authors examine how illustrations can aid learning of text material, focusing on the effects of normal representational pictures on the learning of information in written text. They also consider related research on nonrepresentational pictures, graphic organizers, learner-produced drawings, and mental imagery, as well as other prose learning situations. The review offers guidelines for practice. The study focuses on the effect of illustrations on learning verbal information in written text, limiting the analysis to meaningful, connected discourse, experimenter-provided illustrations, and comparisons between illustrated text and text alone. The research includes a variety of text materials, illustrations, learner differences, and dependent measures. The authors take an information-analysis approach, noting that text and illustrations may contain overlapping information (illustrated text information), information only in the text (nonillustrated text information), and information only in the pictures (picture-only information). Understanding which type of information is tested is crucial for interpreting the effects of text illustrations. Willows (1979) studied reading comprehension of children's stories with and without pictures. An example of a page from the illustrated text is shown. Some text information is also portrayed in the picture. Although the information overlap is not perfect, the authors suggest a "functional equivalence" between the picture and the text. After reading, children were asked multiple-choice questions to measure the learning of illustrated text information and nonillustrated text information. The results showed that illustrations can enhance learning of text information.