Abstract. Confluence criteria for non-terminating rewrite systems are known to be rare and notoriously difficult to obtain. Here we prove a new result in this direction. Our main result is a generalized version of Newman's Lemma for left-linear term rewriting systems that does not need a full termination assumption. We discuss its relationships to previous confluence criteria, its restrictions, examples of application as well as open problems. The whole approach is developed in the (more general) framework of context-sensitive rewriting which thus turns out to be useful also for ordinary (context-free) rewriting.