The use of Light’s criteria to dichotomise pleural effusions into transudates and exudates may not be sufficiently specific. Many transudates can be misclassified as exudates especially in the presence of diuretic use. Therefore, the terminology has shifted to non-malignant pleural effusions. The three commonest causes are related to cardiac disease, renal failure and hepatic hydrothorax. Dual pathologies often co-exist in these patients and accurate diagnosis is essential because the cornerstone of therapy is to treat the underlying cause. If patients remain symptomatic despite systemic therapy, then pleural drainage is indicated. These patients are typically on antiplatelet therapy and can be thrombocytopenic or coagulopathic, which can raise the bleeding risk from interventions. They tend to be prone to infections, have electrolyte derangements and may even be hypotensive. Repeated ultrasound guided therapeutic thoracentesis has been the traditional approach and pleural manometry can help identify lung entrapment. If there is lung re-expansion, chemical pleurodesis with talc can be considered. Pleurodesis success may be hampered if there is ongoing pleural drainage. Indwelling pleural catheters have been licensed by the FDA for the management of non-malignant effusions. Possible complications include infections, symptomatic loculations, catheter blockage and hypoalbuminemia from chronic drainage. Choice of intervention depends on the rate of re-accumulation of pleural fluid, ability to control underlying disease, prognosis, and patient preference. Refractory transudative pleural effusions due to organ failure can have a grave prognosis with a shorter median survival than primary pleural malignancy. Where appropriate, palliation of symptoms should be considered.