The thesis Ego-histories: theoretical alternatives repertoires, dedicated to research into new autobiographical discourses situated in the thresholds between historiography, biography and fiction, aims to build theoretical tools from the review of existing conceptual frameworks. In the analysis of new issues, are highlighted and reevaluated, on the one hand, traditional positions anchored in the unity of the subject, the authenticity of its discourse and referential illusion, legitimized by the dichotomous opposition of conceptual pairs such as real/fictional, authenticity/staging, subject/object. On the other hand, are offered analytical models and descriptive strategies that allow to understand the current autobiographical writing as a hybrid genre, with plural configurations that challenge the autobiographical pact based on the identity between instances of authorship, narrative and the fictional. The very processes underlying the self-reflexive writing itself, are analyzed in the light of new constructivist epistemological convictions (S. SCHMIDT; H. MATURANA) and systemic frames understood as a catalyst of complexity. In the perspective of these concepts are discussed, among others, forms of self-analysis (P. BOURDIEU) and autobiographical projects (E. SAID) converging both in the production of ego-histories responsible for transforming theories in narratives and thus allowing the theoretical melting between observer and observed object, based on the concept of second-order observation. Thus, are tested new links between their particular ideas and insertion them in the contemporary context that escape of traditional relations of causality and emphasize the responsibility of their producers. In a parallel perspective, is analyzed the relation between body and writing and between emotion and experience, vigorously present and resonant as conceptual proposals that do not lose its strength of interpellation by transforming them into mere philosophical abstractions, but they exhibit their power by the option of building a life in the world. Overall, the thesis represents an innovative contribution to the construction of alternative theoretical repertoires that allow to draw up a knowledge appropriate to produce a new settings of autobiographical writings.