Michael Long initially stressed how comprehensible input should be provided, not by the speaker modifying their speech to a learner in isolation, but through interaction between the speaker and the learner (see section 2.3.3.2). Building on Swain's (1985) findings, Long (1991) then developed his view to include the benefits for learners when their own output is subjected to clarification or 'negotiation of meaning' by another speaker.

In this way, Long believes that interactive communication can provide everything that acquisition needs: comprehensible input and feedback on output (cf Klein's 'matching' process - see section 2.1.1.1), all within a communicative context. This approach is what he calls Focus on form, not Focus on formS (the latter involves looking at language forms in isolation from communicative activities):

A syllabus with a focus on form teaches something else - biology, mathematics, ... the geography of a country where the foreign language is spoken, and so on - and overtly draws students' attention to linguistic elements as they arise incidentally in lessons whose overriding focus is on meaning or communication. (Long, 1991: 45-46)

In this way, Long tries to take on board research evidence that acknowedges implicit acquisition in second language development, but which also suggests that explicit attention to form can work, but only when learners are 'ready' - in terms of the development of their language system through implicit acquisition (see section 2.1.4.4).