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Coastal wetlands, long undervalued relative to more visually dramatic ecosystems such as coral reefs or old-growth forests, have emerged in recent environmental research as disproportionately effective carbon sinks per unit area. Mangrove forests, salt marshes, and seagrass meadows collectively store carbon in their waterlogged soils at rates estimated to be several times higher than those of equivalent areas of terrestrial forest, largely because anaerobic, sediment-rich conditions slow the decomposition that would otherwise release stored carbon back into the atmosphere over time. This capacity, sometimes termed blue carbon, has attracted growing attention from both conservation scientists and carbon-offset markets seeking credible, quantifiable methods of emissions reduction. Beyond their climate role, these ecosystems provide storm surge buffering for coastal communities, serve as nurseries for commercially important fish species, and filter agricultural runoff before it reaches open water. Despite these benefits, global wetland area has contracted substantially over the past half century, driven primarily by coastal development, aquaculture expansion, and upstream damming that alters the sediment and freshwater flows wetlands depend upon. Restoration efforts face particular technical challenges not shared by forest replanting: reestablishing the precise hydrological conditions, salinity gradients, and sediment supply that allow mangrove or marsh vegetation to take root can require years of engineering intervention before a site becomes self-sustaining, and restored wetlands frequently take decades to accumulate carbon stores comparable to undisturbed sites. Some conservation economists have proposed that blue carbon credits be priced at a premium relative to forestry-based credits to reflect both the higher carbon density of these ecosystems and the co-benefits they provide, though skeptics warn that verifying long-term carbon retention in shifting coastal environments remains methodologically difficult and that premature market expansion could undermine the credibility of offset schemes more broadly.