The aim of this article is threefold. Firstly, it aims to recall how accessing large scale digitized data resources has qualitatively changed the way of doing morphology. Secondly, it shows that raw data extracted from such resources cannot be used as such and requires in-depth preparation in order to be properly exploited; it also shows that the procedures involved in such preparation have to be carefully made explicit since they have a strong impact on the results of queries submitted to sorted data. Finally, it will be argued that using large scale digitized data does not allow us to disregard speakers’judgements concerning grammaticality, which remain indispensable whenever one needs to determine whether a linguistic form is acceptable or not, but that it puts such judgements in perspective insofar as they have to be compared with what is attested in the data.