Increased global competition and scarcity of resources drives industrial companies to cut costs where energy can be a significant part, not the least for energy-intensive companies. Improved energy efficiency in industry is complex as is regards numerous various energy using processes which are heavily intertwined. One such energy using process is compressed air systems (CAS) which is used in most industrial companies worldwide. With a few exceptions, previous research on barriers to and drivers for energy efficiency has treated energy efficiency improvement measures as one entity. However, since the characteristics of energy efficiency improvement measures differs, technology-specific measures will face different barriers to and drivers for energy efficiency which will affect the investment decision accordingly. The same applies for the non-energy benefits (NEBs) related to energy efficiency improvement measures. The aim of this paper is to study barriers to, drivers for and NEBs for energy efficiency improvement measures in CASs. Carried out as an interview study combined with a questionnaire, the paper results show that the major barriers are related to the investment, e.g. other priorities for capital investments and access to capital. Major drivers are related to in-house energy management practices, and major benefits include productivity gains and avoidance of capital expenditure. Further research is emphasized in the CAS field.