During the past decades, migration policies in Western societies have grown stricter by the day. As part of this retrenchment, migrants are required to pass language tests to gain access to human and democratic rights such as residency, family reunification, and citizenship, as well as to enter the labour market or higher education. The use of language tests to control migration and integration is not value neutral. The question discussed in this paper is whether those who develop language tests should strive to remain neutral, or, on the contrary, whether they have a moral and professional responsibility to take action when their tests are misused. In this paper, a case is made for the latter: arguing along the lines of critical language testing, we encourage professional language testers to take on a more active role in order to prevent harmful consequences of their tests. The paper introduces the concept "language test activism" (LTA) to underscore the importance of scholars taking a more active role for social justice, following the pathway of proponents of intellectual activism in related fields like sociology and linguistics. We argue that language testers have a special responsibility for justice and consequences, as these are integrated in the very concept of validity upon which modern language testing is based. A model of language test activism is presented and illustrated by real-life examples of language test activism in Norway and Italy showing that language test activism may need to take on different forms to be successful, depending on the context in which it takes place.