In the late twentieth century, the Brazilian legal system underwent a series of transformations that resulted in new ways of interpreting civil law. One of the most significant was the proliferation of microsystems (such as the Consumer Protection Code). The success of this venture led lawmakers to apply the same logic to other areas. A little over eight years ago, various bills were proposed that aimed to restructure one of the traditional branches of civil law (family law) by repealing book IV of the Civil Code (which regulates family law) in its entirety and creating a new microsystem: the Family(ies) Act(s). Most find this proposal appealing, as it would change the dynamics in this field. Too often, however, the consequences of such changes are not evaluated from a civil law perspective. The purpose of this paper is to analyze, from a systematic point of view, the benefits (or drawbacks) of creating a new microsystem. Accordingly, it sets out to investigate the reasons that led to the autonomy of this branch of civil law within the current system of codification and analyzes various attempts to create such a microsystem throughout the twentieth century. The advantages and disadvantages of microsystems will be addressed within a broader framework that goes beyond a strictly national outlook (thus placing Brazil into the global context of legal harmonization).

SUMMARY: Introduction – 1. Canon Law and the Autonomy of Family Law – 2. Caught Between Worlds: Public Law and Private Law – 3. Toward the Systematization of Family Law: from Pufendorf to Wolff – 4. Systematic Approaches to Family Law by Hugo and Kant – 5. The Systematic Organization of Family Law in Nineteenth-Century Germany: From Heise to the BGB – 6. The Systematic Organization of Family Law in Brazil – 7. Family Law Conceived as a Microsystem – 8. The Interdisciplinary Essence of the New Systematic Arrangement of Family Law – 9. The Demise of a Codified System in Socialist Law – 10. The Advantages of Preserving the Systematic Arrangement of the Civil Code – 11. Harmonization of Law and Supranational Codes – 12. Harmonization of Law and the Case of BRICS – Conclusion.