This article synthesises progress made in the description of spoken (especially conversational) grammar over the 20 years since the authors published a paper in this journal arguing for a re-thinking of grammatical description and pedagogy based on spoken corpus evidence. We begin with a glance back at the 16th century and the teaching of Latin grammar in England, with its emphasis on "speaking" the target language. Later grammars were dominated by written standards, a situation that persisted till the 20th century, when recording technology and spoken corpora enabled new insights into the grammar of everyday speaking. We highlight those insights which especially challenge grammars derived only or mainly from written sources. We evidence the view that conversational grammar is non-sentence-based, co-constructed and highly interactive, and that it poses questions concerning metalanguage. We briefly review debates concerning spoken grammar and ELT/ESL pedagogy. We then consider 21st-century Internet technologies and e-communication, and implications for the spoken/written grammar distinction, arguing that description and pedagogy may need to undergo further re-thinking in light of the multi-modality which characterises e-language.