The conceptualization of L2 [second language] proficiency has evolved to include a broader range of knowledge, skills, and abilities, prompting L2 testers to embrace new approaches to defining and assessing L2 speaking ability. This review discusses the evolution of L2 proficiency and speaking ability, and suggests scenario-based assessment (SBA) as a promising practice to designing language assessments that can provide a more comprehensive interpretation of one's L2 speaking ability. An example of an online scenario-based academic speaking assessment is illustrated to demonstrate SBA's efficacy and potential.