My dissertation examines the experimental poetry of three periods, the historical avant-garde of the 1920s, the neo-avant-gardes of the 1950s, 60s, and 70s, and the digital avant-garde (from the 1990s until the present), drawing on the works of poets from the Luso-Hispanic world including the Iberian Peninsula and Latin America. Scholars such as Renato Poggioli and Peter Bürger define the avant-garde as radically new and unrepeatable, an "advanced" guard that exhausted its aesthetic and political possibilities. I challenge this view by establishing a continuity of avant-gardes that emerge during periods of technological innovation and cultural exchange, introducing new artistic modalities, engaging with emerging media and re-purposing the strategies of past avant-gardes to their own historical conditions. Experimental poetic practices such as visual, kinetic, phonetic, concrete, video poetry, and poetic performance have unfolded over time and across national boundaries in response to global, social, and technological forces. My focus is on poetry broadly understood as works that "experiment" with the interplay between the visual, the sonorous and the verbal, questioning both genre and medium specificity, and contesting traditional discipline-bound tools of analysis. In order to critically approach poems that are often not printed on a page, and depend on more than verbal communication, I draw on disciplines such as literary analysis--including close-readings--media theory, and film analysis, and deploy theories of metaphor, embodiment and affect to interpret works that focus on the materiality of language through typographic experiments, script animation, and performance. The selection includes poems by authors from the 1920s such as Josep M. Junoy, Joan Salvat-Papasseit, José Juan Tablada, Guilherme de Almeida; neo-avant-garde visual and concrete poets from the 1960s such as Joan Brossa, Julio Campal, Edgardo Vigo, and Décio Pignatari; and their contemporary counterparts working with digital media such as Ana María Uribe, Olga Delgado, María Mencía, Arnaldo Antunes, and Eduardo Kac. Examining digital poetry in the light of older poetic practices, I compare and contrast how artists have queried the status of literature as a purely script-based art, considering how notions of experimental literature have changed through time (diachronically), but also isolate each period (synchronically). / Romance Languages and Literatures