This document discusses listening as an important part of second language acquisition. It argues that listening provides input that allows learners to build a "cognitive map" of meaning in their mind, which may be more important than speaking practice alone. There are two main types of listening discussed: one-way transactional listening and two-way interactional listening. Successful listening relies on both bottom-up processing of linguistic elements as well as top-down processing using prior knowledge and schemata. The document outlines several specific listening challenges and provides suggestions for practice, including working with reduced forms, assimilation, elision, and resyllabification.