Socio-technical approaches have established that ICT-supported standardization of healthcare work is difficult, if not impossible. We argue that standardization is neither straightforward nor uncontroversial, but discuss an interpretative case study where standardization of nursing work--to an interesting degree--has been achieved. Our case suggests that co-constructing of the standards is essential to standardization in practice. This is partly imposed from the top, and partly accomplished through the active involvement and ingenuity of users.