Reading is a process of meaning making that entails a large number of diverse skills. As a complex construct, reading ability has been conceptualized from multiple perspectives, including psycholinguistic, sociocultural, and educational. Beyond the general agreement that learning to read in a second language is a major undertaking, little consensus exists as to what this ability entails, how it develops, and how progress in development can be monitored and fostered. This entry provides the essential foundations for assessing second language reading by first describing the brief history of reading research. The unique nature of reading ability in a second language is then outlined, and the challenges for second language reading assessment are explained. Future directions in reading assessment research include a move away from exclusive focus on language‐specific skills in the target language to encompass nonlanguage‐specific resources available in the learner's first language as well as the knowledge and interests of the learners.