This article explores the challenge of setting performance standards in a non-Western context. The study is centered on standard-setting practice in the national learning assessments of Trinidad and Tobago. Quantitative and qualitative data from annual evaluations between 2005 and 2009 were compiled, analyzed, and deconstructed. In the mixed methods research design, data were integrated under an evaluation framework for validating performance standards. The quantitative data included panelists' judgments across standard-setting rounds and methods. The qualitative data included both retrospective comments from open-ended surveys and real-time data from reflective diaries. Findings for procedural and internal validity were mixed, but the evidence for external validity suggested that the final outcomes were reasonable and defensible. Nevertheless, the real-time qualitative data from the reflective diaries highlighted several cognitive challenges experienced by panelists that may have impinged on procedural and internal validity. Additional unique hindrances were lack of resources and wide variation in achievement scores. Ensuring a sustainable system of performance standards requires attention to these deficits.