<p>Rates of biological invasion are rarely described as a sustainability issue, yet multiple lines of evidence suggest that burgeoning invasion rates cause ecosystems to be less sustainable over time. Field data reveal that as the number of established non-native species (‘invaders’) in an ecosystem increases so does the likelihood that at least one of them will cause, directly or indirectly, an ecological disruption—i.e., a substantial alteration or interruption in ecosystem function. Furthermore, a change in environmental conditions can trigger an initially innocuous invader to become disruptive long after its establishment; invasions can thus have deferred impacts whose nature and timing are unpredictable. Finally, case studies show that invaders can interact with each other and with co-occurring stressors to produce synergistic impacts, although it is not clear how frequent such understudied interactions are in comparison with additive and antagonistic effects across ecosystems. If additive or synergistic impacts are more frequent than antagonistic effects, then increasing colonization pressure (the number of species introduced) can cause ecosystems to become more easily disrupted and difficult to manage over time. Assuming that each new invader, on average, increases the risk of disruption to an ecosystem, then even a small reduction in the invasion rate can benefit ecosystem sustainability.&#xa0;These considerations justify efforts to reduce invasion rates globally, as directed by the Kunming-Montreal Global Biodiversity Framework.</p>