Purpose This study aims to identify problems connected to information classification in theory and to put those problems into the context of experiences from practice. Design/methodology/approach Five themes describing problems are discussed in an empirical study, having informants represented from both a public and a private sector organization. Findings The reasons for problems to occur in information classification are exemplified by the informants’ experiences. The study concludes with directions for future research. Originality/value Information classification sustains the basics of security measures. The human–organizational challenges are evident in the activities but have received little attention in research.