ELLs enter kindergarten with a range of academic, self-regulation, and linguistic skills, but there are clear discrepancies in the achievement of ELLs when compared to non-ELLs. To better understand how to support ELLs as they make the transition to kindergarten, this research brief will: 1. define ELLs under federal laws 2. examine how ELLs are performing on Oregon's Kindergarten Assessment (KA) and 3. examine how English Language Proficiency is related to the performance of ELLs on the Oregon Kindergarten Assessment. (author abstract)