With the increase in workplace English-as-a-Second-Language (ESL) literacy education programs, there is a need to assess whether the attention given to improving basic skills and English language proficiency has made a change in the participant and in the workplace. Such evaluations often use both qualitative and quantitative measures of program outcomes. Qualitative measures include focus groups and individual (stakeholder) interviews, workplace observations, and portfolios of learner classwork. Quantitative measures include commercially available tests, scaled performance ratings, and some program-developed assessment tools, such as portfolios. To increase credibility and help ensure reliability of qualitative measures, evaluators collect multiple types of evidence (such as interviews and observations) from various stakeholders (employers, labor unions, participants, teachers, funders) related to a single outcome and arrange them into matrices, organizing them thematically and enabling analysis of data across respondents. Two commercially available tests that are commonly used sources of quantitative data are the Basic English Skills Test (BEST) and the Comprehensive Adult Student Assessment System (CASAS) ESL Appraisal. These instruments are easy to use, and their reliability has been tested but they may not measure what has been taught in the classroom, and they may have little applicability to specific workplace tasks. Other issues surrounding evaluation of workplace ESL instruction are these: unrealistic stakeholder expectations; the need for additional, cross-cultural training in techniques for success in the American workplace; and inadequate funding. Contains 12 references. (MSE) (Adjunct ERIC Clearinghouse on Literacy Education)