Chronic pain in fibromyalgia patients, together with its associated symptoms and co-morbidities, is now considered a result of dysregulated mechanisms in the central nervous system (CNS). As fibromyalgia patients often report sleep problems, the physiological processes that normally regulate sleep may be disturbed and overlap with other CNS dysfunctions. Although the mechanisms potentially linking chronic widespread pain, sleep alterations and mood disorders have not yet been proven, polysomnography findings in patients with fibromyalgia and non-restorative sleep and their relationships with clinical symptoms support the hypothesis of a conceptual common mechanism called 'central sensitisation'. Food and Drug Administration (FDA)-approved drugs for the treatment of fibromyalgia may benefit sleep, but their label does not include the treatment of fibromyalgia-associated sleep disorders. Non-pharmacological therapies (including a thorough sleep assessment) can be considered in the first-line treatment of non-restorative sleep, although they have not yet been fully investigated in patients with fibromyalgia. Both pharmacological and non-pharmacological treatments should be used cautiously in patients with fibromyalgia, bearing in mind the patients' underlying disorders and the potential interactions of the therapies.