The potential value of Middle English bynames for the history of English vocabulary has long been recognised, and occupational names have been given a good deal of scholarly attention. Nevertheless there are many borough and city records whose bynames have yet to be systematically researched. The present paper on methodology and its sequel, Part 2, ‘Etymologies’, are concerned with occupational bynames in the borough court rolls of late medieval Nottingham. ‘Etymologies’ will discuss 51 bynames that either are not recorded as occupational agent nouns in the Middle English Dictionary (hereafter abbreviated as MED), antedate the earliest quotation in MED, or, through their forms and contexts, shed new light on the etymology or sense of the source word. Part 1, ‘Methodology’, places this investigation of Nottingham bynames against the background of previous lexicographical applications of Middle English bynames, describes the contents of the Nottingham borough court rolls, and sets out the methodological principles and practicalities that influence the etymological judgements made in the second paper. Lacking the linguistic contextualisation that is normal for items of vocabulary, bynames present special problems of interpretation for the lexicographer, which need to be identified and, where possible, mitigated.