Assessment literacy (AL) empowers teachers (Grabowski & Dakin, 2014) by helping them make better decisions about the development, administration, and use of assessments (Harding & Kremmel, 2016; Popham, 2009). This is crucial because when teachers make erroneous interpretations, which lead to incorrect decisions, students can suffer unintended, negative consequences (Purpura, 2016; Purpura, Brown, & Schoonen, 2015). As essential as AL is to providing quality teaching and learning opportunities, assessment education remains inadequate (Lam, 2015; Mendoza & Arandia, 2009; Vogt & Tsagari, 2014). According to Cheng (2001), teachers spend up to a third of their time in assessment related activities; however, most "do so with little or no professional training" (Bachman, 2000, p. 19-20). In light of the demand for the development of instructor AL, this paper first defines and conceptualizes language assessment literacy (LAL). Then it problematizes LAL through an investigation of empirical studies conducted to explore pre- and in-service teacher education and resources that have been used to develop teachers' LAL. Finally, it examines how teachers' LAL levels are evaluated through assessments such as Cambridge University Press's Teaching Knowledge Test, the edTPA, and state teacher certification Praxis tests.