This paper analyzes preverbal overt subjects, comparing Brazilian Portuguese to (other) null-subject languages, especially within Romance. It explores syntactic and semantic properties, including resumption, ellipsis, quantifiers and scope, variable binding, ordering restrictions, pronominal distinctions, minimality violations, bare nouns and definiteness. It concludes that preverbal subjects in Brazilian Portuguese can be realized both in argumental positions (Specifier of the Inflectional or Tense Phrase) and non-argumental positions (Topic Phrase specifiers), with the possibility that both types of positions are filled by the subject in the same clause, incorporating properties that have been argued not to be found together in other languages. KEY-WORDS: Portuguese; minimalism; subjects; comparative syntax. A., 23:esp., 2007 (113-146) * It is a great pleasure for me to have the opportunity to contribute some of my work to a volume in honor of Lucia Lobato. I am very grateful to have counted with her encouragement and friendship for many years. During her career, Lucia Lobato made crucial contributions to linguistics in Brazil, by means of her research, and by teaching and advising many students who went on to follow careers in the field. She was an extremely dedicated teacher and mentor to her students, and her own work inspired many of them in different ways. Her efforts to promote the interaction among linguists in Brazil and abroad also contributed significantly to the development of the field in Brazil. I hope Lucia's efforts and dedication to linguistics remain an inspiration to Brazilian linguists for a long time. I would like to thank the editors of this volume, Cilene Rodrigues and Ana Paula Scher, for taking the time to edit this collection of papers in honor of Lucia Lobato, and for inviting me to contribute this paper. Thanks also to my research assistants: Gerardo Fernández-Salgueiro, for surveying part of the relevant literature on the analysis of subjects which I refer to in this paper, especially regarding analyses previously proposed for Spanish; and Amanda Gallaher, for helping with the final proofs. RESUMO: Esse artigo analiza sujeitos preverbais manifestos, comparando o português do Brasil com (outras) línguas de sujeitos nulos. O artigo investiga propriedades sintáticas e semânticas, incluindo pronomes resumptivos, elipse, quantificadores e escopo, ligação de variáveis, restrições de ordem, distinções pronominais, violações de minimalidade, nomes sem determinantes, e definitude. Concluo que esses sujeitos preverbais podem realizarse tanto em posição argumental (especificador do sintagma flexional ou temporal) quanto em posições não-argumentais (posições de tópico), com a possibilidade de os dois tipos de posições serem preenchidos pelo sujeito na mesma oração, incorporando propriedades que são tidas como não ocorrendo juntas em outras línguas.