Depression is common, serious and treatable. The Australian and New Zealand Clinical Practice Guideline for the Treatment of Depression by Specialist Services provides evidence-based treatment guidance across the spectrum of depressive disorders and delineates where specialist treatment and primary care management is indicated. The present summary version covers the key contents of the guideline. It includes assessment, treatment and general management issues by category type and severity of depressive disorder. Algorithms of first-line and subsequent treatment choices are provided for: (i) mild depression without complications; (ii) moderately severe depression (including with comorbid anxiety) and dysthymia; (iii) uncomplicated, melancholic or atypical depression; (iv) moderately severe depression with comorbid substance abuse; (v) moderate to severe depression with physical disorders; (vi) severe depression with melancholia; (vii) recurrent depression or failure to respond to a preferred first-line treatment; and (viii) psychotic depression, and severe depression with risk of suicide. Continuing and maintenance treatments for recurrent depression are discussed. Emerging evidence of the equal value of cognitive behaviour therapy (CBT) and interpersonal psychotherapy (IPT) to pharmacological treatments for some depression is discussed, and the need to ensure that they are provided by suitably trained practitioners. Indications for hospitalization and electroconvulsive therapy (ECT) are also provided.