Abstract Given the important role that properly designed sustainable management accounting (SMA) may play in helping firms to face their social and environmental responsibilities better, there is little evidence about how management accounting system to support sustainable decisions-making within companies. We suggested a consistent system of SMA, which could be used to study the research topic empirically. An experimental study was carried out focusing on the basic idea that whether the availability of sustainable cost information affects the willingness of managers to take sustainable considerations into account in their sustainable decisions and to align their processes with sustainability goals in the context of two alternatives of company s' accounting systems. Data collected by taking responses from a variety of managers in a sample of large companies operating in Egypt. The evidence reported here reveals that when sustainability cost information is available to managers at various stages of the supply chain, they are more willing to take sustainable decisions and align their processes with sustainability goals in the case of using the alternative of SAMS. We leverage these findings into a series of research questions to stimulate the interests of accounting academics for future accounting or interdisciplinary research in sustainability. These results have several implications for public policy in Egypt and accounting practice. Also, it allows researchers to develop a better theory of how to build decision-focused sustainability management accounting system to improve competitiveness and create long-term firm value.