When teachers hear the word ‘cohesion’, they usually think of grammatical cohesion—an aspect of cohesion reasonably well covered in student books and teacher materials. However, occupying an area that straddles both lexis ‘proper’ and cohesion lies ‘lexical cohesion’. In what follows, it is argued that the teaching and learning of certain aspects of lexical cohesion is problematic, and that this state of affairs may be behind the current neglect of this subject in EFL materials and classrooms. The paper begins with a brief overview of Halliday and Hasan's (1976) classification of lexical cohesion, and then looks, in turn, at four types of cohesive device. Learners’ uses of these different cohesive ties are discussed, the obstacles to correct usage are noted, and suggestions are made as to how teachers can help students to develop this aspect of their writing.