One of the largest emerging threats to forest biodiversity worldwide is the spread of shade-tolerant woody invaders, which are able to establish and outcompete native forest species even in relatively undisturbed conditions. Case studies in both tropical and temperate forests indicate such invaders often combine shade tolerance and fast growth to a degree that is rare in native species, and point to a ‘forest invader syndrome’ that may unify invasion processes across latitudes. However, invasion research in temperate and tropical ecosystems remains poorly integrated, in part because management strategies are often focused on particular species that are unique to tropical or temperate habitats. This division has stymied theoretical advances in invasion research that could arise from a synthesis of invader behavior across regions, and impeded the development of shared invasion management strategies. This organized oral session will bring together six scientists working on woody invasions of closed-canopy forests in temperate and tropical ecosystems. Our goal is to foster discussion on commonalities of mesic forest invasions as a means to better develop a theory of plant invasions in shaded habitats. For example, comparison of functional traits and demographic attributes of invaders may allow identification of a syndrome of traits common to invaders of closed-canopy forests that could be used for invader prevention in risk assessment protocols. In addition, participants will discuss whether particular native forest attributes, such as preservation of a vigorous native understory layer, reduce the invasibility of introduced shade-tolerant species. Represented ecosystems include tropical evergreen forests in Australia and the Caribbean, subtropical seasonal forests in South America, and cold-deciduous forests of Eastern North America and central Europe. Forest ecology has long been an important research theme of ESA members, and forest invasions are of worldwide ecological significance due to their association with native biodiversity decline. There is a dire need to integrate research findings across disparate habitats, and between researchers of diverse perspectives. We view this session as an opportunity for dialogue in basic science between researchers that rarely get to interact.