Deltaic subsidence constitutes a classic geological problem, with implications for the accumulation of resource reservoirs as well as coastal degradation associated with accelerated relative sea-level rise. Therefore, disentangling the driving processes and quantifying the rates of subsidence has become a high priority, resulting in a flurry of research in and near the Mississippi Delta in the post-Katrina era. This presentation offers insights into the vigorous debate that has ensued, by means of a discussion of the relative importance of shallow versus deep crustal processes. This includes a review of isostatic adjustments associated both with local sediment loading and the aftermath of the last deglaciation, faulting, sediment compaction, and fluid extraction. It is shown that rapid progress on this complex issue is currently being made, with the potential for a new paradigm for deltaic subsidence in this region to emerge.