Hoarding seems to be a non-specific symptom, as it has been associated with a wide range of psychiatric disorders. Validating hoarding as pathological is controversial and its nosological status remains unresolved. ‘Diogenes syndrome’ has been paradigmatic in this area, but its clinical use seems limited. Hoarding is not explicitly covered in either DSM–IV or ICD–10 and literature suggests that diagnosis of mental illness may consequently be missed in this population. In the context of these theoretical uncertainties, clinicians still need to accurately assess and treat patients who show hoarding behaviour. To this end, we summarise the available evidence, and present assessment and management algorithms together with a multicomponent psychological intervention that aims to teach patients to successfully apply the three Rs (reduce, recycle, reuse).