Areas covered: This review focuses on, and critically appraises, the clinical efficacy and safety of ambrisentan as well as its pharmacokinetic and pharmacodynamic properties. The article also gives an expert perspective on the role of ambrisentan in the management of PAH. Expert opinion: Ambrisentan is an effective and safe treatment which is, in the authors' opinion, a valuable addition to the armamentarium against PAH. Ambrisentan offers a relative lack of drug interactions, once daily dosing and reassuring liver safety, offering safety and convenience advantages over bosentan. Presently, there is a lack of comparative studies between PDE5 inhibitors and endothelin receptor antagonists and a lack of data comparing bosentan with ambrisentan. This is hindering data-based conclusions regarding relative efficacy and further studies are needed to define the role of ambrisentan in the management of PAH.