The US National Park Service mission includes conserving native species and historical landscapes ‘unimpaired for the enjoyment of future generations’. However, humans have increased the introduction of non-native species that can become invasive and which have harmful impacts on native species and landscapes. We revisit two previous papers, ‘Alien Species in National Parks: Drawing Lines in Space and Time’, published in 1995 by D.B. Houston and E.G. Schreiner, and ‘Climate Change and “Alien Species in National Parks”: Revisited’, published in 2014 by T.J. Stohlgren, J.R. Resnik and G.E. Plumb, to demonstrate the organizational progress that has been made in reducing impacts of invasive species despite the increasing pressure of increasing numbers of non-native species. The National Park Service has continued efforts on invasive plant management, established an Invasive Animal Program in 2018 and developed a Pest & Invasive Species Project Kit to compile information to inform management regardless of taxonomic group. Additionally, the Park Service has expanded their toolset to make decisions related to invasive species and climate change to focus on achievable goals. Since the 1995 publication, the scale of invasion has increased, and impacts of climate change are more noticeable since the 2014 publication, increasing the complexity in trying to achieve the National Park Service mission.