Primary aldosteronism (PA) is a condition well worth detecting because it is a common cause of hypertension and is associated with excessive morbidity for the degree of hypertension and reduced quality of life, all of which can be abrogated with specific surgical or medical treatment. Recent years have seen an explosion in knowledge concerning the genetic bases of this disorder, and particularly of somatic mutations associated with aldosterone-producing adenomas and germline mutations causing rare familial forms, both involving genes encoding ion channels. Inroads have also been made into understanding molecular pathways that may be involved in the development of PA. With evidence continuing to mount for non-blood pressure-dependent adverse effects of aldosterone excess and for superior effects of specific over non-specific treatment, the need for accurate yet readily applicable and available diagnostic approaches and methodologies has become a matter of urgency. Advances in approaches to confirmatory testing, subtype differentiation, and assay methodology are helping to improve feasibility and reliability of the diagnostic workup for PA, and new treatment approaches are emerging.