Information technologies (IT) are widely used in healthcare, however, little is known about the usability of nursing information systems. This article reports an evaluation study that aimed at researching the usability of four electronic nursing record (ENR) systems and thereby providing guidelines for further IT development. For the purposes of the study the concept of usability was defined to cover the following aspects: nurse-computer interaction in working context, information exchange, and collaboration between healthcare professionals. The study utilized two usability research methods, contextual inquiry and expert review, and was conducted with 18 nurses in Finland. Study results showed that the ENR systems share several usability problems in common, most of them relating to the efficiency of use, intuitiveness, and poor fit for multi-professional needs. Nurses had mainly negative experiences on documenting practices with ENRs: documentation requires a lot of resources, patient information is hard to find, and procedures do not meet the contextual needs. These findings suggest usability problems having significant effects on nurses' documentation practices and nursing work.