This article explores parallels in the dimensions of microvariation characterizing the functional structure and organization of the Romance nominal and clausal groups. Within a parameter hierarchy approach it is argued that observed synchronic and diachronic variation across both domains can be readily captured in terms of a single set of higher- and above all lower-level parametric options. This parallelism constitutes a welcome finding in that it points to how the available parametric space can be constrained and defined in terms of a set of common transcategorial principles and options.