Burgeoning global demand for products derived from seaweeds is driving the increased removal of wild coastal seaweed biomass, an emerging low trophic level industry. These products are marketed as organic and “sustainable.” Brown macroalgae, such as kelps (Laminariales) and rockweeds (Fucales), are foundational species that form underwater forests and thus support a diverse vertebrate, invertebrate, and algal community—including important commercial species—and deliver organic matter to coastal ecosystems. The measure of sustainability used by the rockweed (Ascophyllum nodosum (L.) LeJolis) industry, maximum sustainable yield, accounts for neither rockweed's role as habitat for 150+ species, including species of commercial or conservation significance, nor its role in coastal and estuarine ecosystems. To determine whether rockweed cutting is “sustainable” will require data on the long-term and ecosystem-wide impacts of cutting rockweed. Once a sustainable level of cutting is determined, strict regulation by resource managers will be required to protect rockweed habitat. Until sustainable levels of cutting and appropriate regulations are identified, commercial-scale rockweed cutting presents a risk to coastal ecosystems and the human communities that depend on those ecosystems.