Over the past few decades, those who take tests in the United States have exhibited increasing diversity with respect to native language. Standard psychometric procedures for ensuring item and test fairness that have existed for some time were developed when test-taking groups were predominantly native English speakers. A better understanding of the potential influence that insufficient language proficiency may have on the efficacy of these procedures is needed. This paper represents a first step in arriving at this better understanding. We begin by addressing some of the issues that arise in a context in which assessments in a language such as English are taken increasingly by groups that may not possess the language proficiency needed to take the test. For illustrative purposes, we use the first-language status of a test taker as a surrogate for language proficiency and describe an approach to examining how the results of fairness procedures are affected by inclusion or exclusion of those who report that English is not their first language in the fairness analyses. Furthermore, we explore the sensitivity of the results of these procedures, differential item functioning (DIF) and score equating, to potential shifts in population composition. We employ data from a large-volume testing program for this illustrative purpose. The equating results were not affected by either inclusion or exclusion of such test takers in the analysis sample, or by shifts in population composition. The effect on DIF results, however, varied across focal groups.