Agreement is a syntactic mechanism involving morpho-syntactic categories such as person, number, gender. Since morphology provides the formal means for this syntactic mechanism to result in surface contrasts, the impact of morphology on agreement is usually limited to the (trivial) fact that the signalling of agreement stays and falls with (the contrast between cells of) the morphological paradigms whose cells are defined through distinct morpho-syntactic feature values.
However, it sometimes happens that pure morphology (e.g. [contrasts in] inflectional classes) conditions change in agreement rules and/or in morpho-syntactic properties of the language such as, say, the number of genders occurring in the system. In this paper, I will review some such cases from lesser-known Romance varieties.