In Europe, commercialisation of macroalgae remains in its infancy: most producers are small-scale, with biomass applied predominantly in niche or low-volume product. The potential range of mainstream industrial applications of macroalgae is far-reaching, from bio-stimulants and feed additives to meat replacers, nutraceuticals, cosmeceuticals, pharmaceuticals, and biomedical devices. Remaining bottlenecks to upscaling the industry include the development of robust, highyield seed material; high-volume pre-processing and biorefinery; product development; as well as industry-, regulatory- and consumer acceptance. The SeaMark (“Seaweed-based market applications”) project will identify, develop, and exploit concrete solutions to all of the above bottlenecks, thereby accelerating the upscaling of the industry to achieve commercial scale across multiple market sectors in a cascading biorefinery approach. Work Package 7 of the project is dedicated to the development of a Go-to-market strategy, including the establishment of an Industry Purchasing Group (IPG) to identify and understand producer, processor and end-user needs, predominantly in the B2B (businessto-business) domain. The current paper sets out a plan for the technical facilitation of interactions between producers and industry players from processors to distributors. The proposed platform(s) will maximise accessibility of market knowledge to key stakeholders through mutual learning exercises and enable business model co-development. The study analyses and compares multiple online platform solutions through simple SWOT (strengths, weaknesses, opportunities, strengths) analysis to aid selection of a platform which delivers the most short- and long-term impact within the scope of the project. The paper then lays out a methodology for the creation of the platform(s) and identifies requirements including ongoing maintenance and exploitation post-project, as well as recommendations for further elaboration of the platform(s) into a commercial B2B marketplace for seaweed biomass.