Acute heart failure (AHF) represents rapid or gradual onset or worsening of symptoms and/or signs of HF, reflecting diverse abnormalities of congestion and/or hypoperfusion status, leading to either unplanned hospital admission, emergency department (ED) visit or outpatient visit. In patients with history of HF, escalation of therapies, irrespective of venue of care, identifies worsening HF episodes. Diagnosis must start at the time of the first medical contact and should be based on clinical judgment to integrate patient history with physical examination. Since the sensitivity and specificity of symptoms and signs are only modest, diagnosis of AHF should be further confirmed by appropriate additional investigations such as biomarkers, ECG, chest X-ray, lung ultrasound, laboratory assessment and echocardiography. Coexisting life-threatening clinical conditions that require urgent correction need to be immediately identified and managed, before any other therapeutic measures. The diagnostic workup should continue with the identification of clinical phenotypes, Acutely Decompensated HF (ADHF), Acute Pulmonary Oedema (APO), Acute Right Failure (ARF) and Cardiogenic Shock (CS), that would support the initiation of the early individualized treatments. Management of AHF represents a continuum of evaluation, initiating therapies, assessing response to implemented therapies and creating a plan for the immediate, short and medium term care.