This study, in two parts, endeavors a novel analysis of existential constructions, based on a different theoretical setting of clause structure, where the predicate is taken as a necessary and sufficient constituent of the clause. Leaning on this perception, the analyses of existential constructions developed here tries to overcome the discrepancy between form and (semantic and informational) meaning in Hebrew existential constructions. The main part of the study deals with affirmative existential-presentative constructions, used to introduce referents into the discourse. Most of the constructions have been analyzed as consisting of an existential constituent, viewed as a modal marker, and a pivot, regarded as the core component of the predicate domain. This analysis is shown to be valid for both the existential marker jeʃ and for its suppletive verbal forms, derived from √hjj ‘be’. A distinction is made between verbal forms with non-referential and referential verb-bound person markers, where the latter, found with expected, known or given pivots, function as focus marking devices, coming in complementary distribution with prosodic marking of focus. Thus, presentative-existential sentences are formed as unipartite sentences, consisting of only a predicate domain. The last two sections of Part I deal with constructions where the existential constituent follows the pivot and with constructions where the pivot is definite. Part II deals with other existential constructions, including negative constructions; bipartite existential sentences; existential constituents as sole constituents in a sentence; existential constituents with clitic referential markers; and the use of existential markers as interjections or discourse markers.