This paper briefly outlines some problematic points in the design of XML-based standards for e-commerce. The source of these problems is found in the difference between EDI-based e-commerce and the more open forms of XML-based e-commerce. The Internet and the globalisation of the economy has fundamentally changed the legal situation of electronic commerce. EDI-based commerce often was the continuation of established business relations, relations in which legal issues had already been solved and handled in a satisfactory manner. In the more open forms of XML-based commerce, such as the ones we see in electronic marketsplaces, this is not always the case. On the contrary: often the parties doing business will never have encountered each other before. This changes the legal assessment of the situation and will – if unnoticed – lead to some difficult problems.