OBJECTIVES: In the absence of any pulmonary arterial hypertension (PAH)-specific PRO instruments developed in accordance with 2009 FDA guidance requirements, this qualitative research study was conducted to develop a new instrument assessing PAH symptoms and their impacts following the PRO guidance. METHODS: Patient inclusion criteria were age 18–80 years and symptomatic PAH (WHO Group 1) diagnosed by right-heart catheterization. Concept elicitation was based on 5 focus groups, after which saturation of emergent concepts was reached. A PRO instrument for PAH symptoms and their impacts was drafted, considering input from the international Steering Committee as well as translatability and legibility assessments. Two rounds of cognitive interviews on the draft PRO were conducted, with instrument revisions following each. The study was approved by institutional review boards at 5 US sites and participants provided written informed consent. RESULTS: Focus groups comprised 25 patients, and 20 additional patients participated in cognitive interviews (10 per round). Participants had a mean±SD age of 54±16 years, were predominantly female (91%), and were diverse in race/ethnicity, WHO functional class (FC I/II: 51%, III/IV: 49%), and etiology (associated PAH: 51%, idiopathic PAH: 47%, familial PAH: 2%). The draft PRO instrument was found to be clear, comprehensive, and relevant to PAH patients in cognitive interviews. Items were organized in a draft conceptual framework with 4 symptom domains (respiratory symptoms, tiredness, cardiovascular symptoms, other symptoms) and 5 impact domains (physical activities, daily activities, social impact, cognition, emotional impact). The recall period is the past 24 hours for symptom items, and 7 days for impact items. CONCLUSIONS: The draft instrument was shown to capture symptoms and their impacts relevant to PAH patients, demonstrating content saturation and concept validity. Additional testing is needed to confirm the content and psychometric validity of the PAH-SYMPACT before use in future clinical practice or studies.