The contribution explores intra-individual (IAV) as well as intra- textual variation in historical legal writing from the perspective of diachronic Construction Grammar. It develops a usage-based model of constructional change and phenomena of variation inevitably associated with it. On the one hand, the understanding of IAV (in historical collaborative writing) will be clarified on a theoretical level, especially in contrast to intra-textual variation. Historical legal texts are often the product of different writers. Variation can thus be found both within passages originating from one scribe and within a text as a collaboratively created written document. The relationship between IAV and stylistic variation is also dealt with in this context; not every case of IAV is social-symbolically motivated. On the other hand, the contribution presents - based on these theoretical discussions - results of a qualitative corpus analysis of complex constructions, whose different realisations (= constructs) clearly represent examples of IAV. The basis for this is a corpus consisting of Middle Low German (MLG) codifications of urban and land law from the late Middle Ages and Early Modern Period. It is shown that IAV can be traced back to the realisation of constructions of different ages (within individual writing) belonging to one constructionalisation path. Related constructions of different ages coexist - even cognitively. This applies, for example, to a large number of subordinative form-meaning pairs, which the chapter examines. From this, considerations of constructions as gradient categories are developed. The synchronous gradience of complex constructions is due to diachronic graduality, i.e. to successive changes in this area. In addition, the contribution investigates the stylistic dimension of lexical alternation on the basis of the underlying legal documents. In this context, slot fillings of selected complex constructions (especially in the most recent land law) will be examined. Here the social-symbolic significance of IAV comes into focus. Overall, the contribution argues in favour of integrating IAV more strongly into the Construction Grammar field of view.