With the rising importance of environmental sustainability, there is a growing need for solutions. Some research indicates that Sweden is performing well in environmental sustainability and the Swedish concept of lagom has been trending in recent years due to its usefulness in leadership. This thesis aims to determine if‘lagom’ can be the key to a sustainable business by examining how the concept is implemented in Swedish companies and how it affects them. Based on the literature review, five semi-structured interviews were held with Swedish business professionals, where questions regarding sustainability, lagom, business culture, and leadership culture were covered. After an analysis of the empirical findings, a correlation between lagom and improved sustainability was found in various aspects. The implementation of trial-and-error was found to be a contributing factor that promotes sustainability. Further, the subconscious cultural influence was also a contributing factor to promote sustainability as the Swedish cultural values promote Laget före jaget (The team before the self), which is incorporated on a societal level. The results would indicate that ‘lagom’ could be a useful aspect to improve sustainability, and potentially of the keys (not the only one) for sustainable business. Although lagom as a concept could be implemented in non-Swedish companies, it is rooted as a Swedish cultural value and is likely not as effective if implemented somewhere where these values are not present. However, due to the nature of the research, this cannot be concretely verified and a need for a case study with several non-Swedish companies would be required to find the true usefulness of lagom.