In designing teaching materials for Open University students' use, authors have been encouraged to incorporate in-text questions to assist students in understanding the materials. These are relatively simple, limited-scope questions relating directly to the preceding material, and are called enabling questions. These are contrasted with the broader self-assessment questions. This study was undertaken to learn whether the in-text questions are serving the authors' purposes of making the material more accessible to students, and whether it is understood how students use this technique. Arguments for and against the use of this device are reported and the literature reviewed. It is concluded that currently available research does not provide a clear and useful picture of students' use and perception of in-text questions, or of the ways student responses correspond to the authors' intent. Some evidence was uncovered that the questions have negligible or negative effects, suggesting urgent need for further research. A list of references is appended. (MSE)