This chapter provides a fresh empirical examination of the interpretations and structures of the focalizing ser (FS) construction in Spanish and the emphatic shi structure in Mandarin Chinese. Its findings support Belletti’s (2004) claim that the TP-internal domain contains a focus projection, similar to what has been argued regarding sentences’ left periphery (CP). We report that these two typologically unrelated languages both allow TP-internal focus projections, before going on to explore the language-specific similarities and differences among various sentences containing ser and shi. Finally, we propose that both ser and shi acquire discourse functions to express focus information in a specific, systematic way.