Number agreement depends on two kinds of information: grammatical and conceptual information. And, generally, they converge. However, for collective nouns, syntactic and conceptual number do not match. When collective nouns are involved in coreference establishing, the pronoun agrees with the noun’s conceptual number, thus creating a number disagreement (e.g. the bandSG played last night. TheyPL were great). This PhD Thesis aims to investigate how conceptual number affects coreference establishing and we explore such linguistic phenomena in both Brazilian (partial pro-drop) and European Portuguese (pro-drop). We also investigate whether intra and inter-sentential processing affects the way conceptual number influences coreference establishing.