This study identifies hidden artefacts in a public organisation. In contrast to earlier studies, itfocuses on artefacts as concealing rather than conveying meaning. Negligent behaviour causedby an unpopular culture was recognised in five psychiatric wards at a Swedish universityhospital. Data comprising observations (87 h) and interviews (n = 60) were collected over aperiod of 48months (2008–2011). Four different items used in everyday work representing adeeper meaning of the organisation were identified during the observations. The items selectedwere work attire, nametags, keys and restraint beds. These were considered particularly promisingwhen it came to the aim of the study, namely, to find out how artefacts are camouflaged. Theobservations and the interviews revealed that these were controversial and contested artefacts inthe organisation. The study uses the term ‘cultural camouflage’ for behaviour that ignores andconsciously conceals symbols that have negative values. This concept contrasts with previousresearch that shows how artefacts are emphasised and how they contribute to the character ofthe activity in a transparent way. Conservative and backward-looking behaviour among staffprovided one explanation as to why artefacts were concealed. Another was the need to establishharmonious internal interactions.