Advocacy is widely expected of teachers working with multilingual learners (MLs) and is included in TESOL standards and teacher education scholarship. Recent research on language teacher advocacy demonstrates the importance and necessity of advocacy for MLs and their families. However, few studies document how teachers collaboratively advocate for their MLs and how they develop collaborative alliances to implement their advocacy. This article contributes to the growing conversation of how teachers advocate collaboratively for MLs by examining a cohort of teachers from their English as a second language (ESL) certification courses into their teaching practice. Dialogic discourse analyses of 3 years of discussions show how teachers develop their community advocacy plans and stances collaboratively. The authors conclude with implications for preparing teachers to advocate collaboratively for MLs and their families.