Understanding successful invasions across taxa and systems in a unified framework is a central goal of biological conservation. While the environmental niche is a promising concept to improve our understanding of biological invasions, existing studies have not applied it to comprehensively examine all invasion stages. Here, we provide a framework that integrates the environmental niche and invasion process at both the species and the population level. By elucidating how species and populations perform in the niche space, we demonstrate how different dimensions of species niches can help in understanding inter- and intraspecific variations in the success and impact of non-native species, and identify knowledge gaps. The niche framework also offers flexibility in integrating other factors driving the success and impact of non-native species.