The authors of the Common Core State Standards and publishers of literacy programs focus on an essential aspect of comprehension, the process of drawing inferences. An inference refers to any piece of information that an author does not include in text but expects readers to use to make meaning. Four common inference types are anaphoric, background knowledge, predictive, and retrospective. To date, there have been group-administered test for teachers to use to evaluate children's abilities to draw inferences, but none focuses on these inference types. The purpose of this study was to create a reliable instrument, and the Assessment of Inference Types (AIT) was the result. It includes four passages, two narrative and two informational. Each passage has eight items, two of each inference type. Unlike most assessments, it measures students' abilities to make inferences moment-by-moment during the act of reading, instead of before or after. The AIT was administered to a 492 fifth graders and was shown to have a .902 reliability coefficient. Armed with results of this test, teachers can identify what specific inferencing processes children have mastered and ones with which they are struggling, and plan instruction accordingly.