This study reports on an analysis of questions which were used in the pursuit of understanding in three focussed discussions, two by native speakers (NSs) and one by non-native speakers (NNs). Twelve adult subjects, four NNs and eight NSs, were used. In 66 minutes, only 30 questions were used for the purpose of pursuing understanding. These questions were classified as open questions, leading questions, challenges, and softened assertions. It was found that the forms used for these four functions varied systematically along a cline of forms ranging from more to less assertive. the NNs selected less assertive forms than the younger NSs, and the younger NSs selected less assertive forms than the older NSs. Age, cultural background, and role of questioner in the discussion may affect the selection of form, but generalizations can be made applicable only to these subjects. It is not known to what extent the subjects typify the various groups in which they hold membership. However, it can be stated that different groups of speakers, using the same linguistic resources, shape the discourse in different ways, according to features in the context. Such information about what is happening at discourse level has significance for the teaching and learning of English for both NSs and NNs. (Author/AMH)