This paper proposes a "Backdoor" Predominant-Dominant-Tonic (P-D-T) paradigm which contextualizes and clarifies the function of the "Backdoor Progression" ♭VII7-to-Imaj7 in tonal jazz. While the function of the ♭VII7 Backdoor Dominant remains in dispute in theoretical and theoretical-pedagogical discourses dedicated to jazz harmony, we argue for its dominant- function conceptualization, which we establish through the introduction of a predominant corollary, IVmaj7, into the harmonic paradigm. We contend that if the II-V-I paradigm represents the archetypal P-D-T progression in jazz, then IV-♭VII-I represents a functionally equivalent Backdoor counterpart established first by its consistent appearance in the repertoire and secondly through speculative discourse concerning dominant functionality. We detail the myriad harmonic models derived from the IVmaj7-♭VII7-Imaj7 paradigm and conduct fresh analyses of familiar jazz standards to demonstrate the ways in which the elucidation of an extensive Backdoor P-D-T paradigm has the potential to inform jazz practice and pedagogy.