Cost accounting has developed differently across countries due to cross-national variance in national financial reporting systems, education and culture. Differences in cost accounting impede a uniform and coherent business management in multinational companies. For this reason it is necessary to sensitize practitioners for national specifics in cost accounting. This study empirically shows that significant differences prevail between German and Japanese cost accounting systems due to variances in national culture and the education of cost accountants. It further provides recommendations for practitioners how to install successful cost accounting systems.