Biodiversity often brings to mind animals and terrestrial plants, but there’s also a hidden gem beneath the waves: marine kelp forests. Covering one-third of the world’s coastlines, these fast-growing seaweeds offer crucial ecosystem services, such as absorbing carbon, oxygenating the water, and providing habitats for over 1500 species. However, kelp forests have declined by up to 60% in the past half-century, threatened by climate change, pollution, and overgrazing. This chapter explores the urgent need for kelp forest restoration, highlighting successful efforts around the world. By reviving these underwater forests, we not only restore biodiversity but also strengthen our fight against climate change, offering sustainable solutions for both ecosystems and coastal communities.