Self-service technologies (SSTs) have enhanced the role technology plays in customer interactions with firms, yet instruments that systematically measure the service quality of SSTs from the perspective of customers remain underdeveloped. Based on psychometric scale development approaches, this study conceptualized, constructed, refined, and tested a multiple-item scale that examined key factors influencing SST service quality. Through qualitative and quantitative studies in four separate phases, a 20-item seven-dimension SSTQUAL scale was developed that includes functionality, enjoyment, security, assurance, design, convenience, and customization. The scale demonstrates sound psychometric properties based on findings from various reliability and validity tests as well as vigorous scale replications across industries and consumer traits using several different samples. The utility of the proposed scale is discussed for implications, limitations and future research. (C) 2011 New York University. Published by Elsevier Inc. All rights reserved.