Responding to a gap in relevant literatures, this study explores cooperating teachers' perceptions of their roles and responsibilities as contributors to the practicum experiences of preservice teachers of English as a second language who were pursuing a master's degree. Research tools featured focus group and individual interviews with 11 cooperating teachers who were working with practicum students. Findings include a perceived lack of communication between cooperating teachers and practicum course instructors, inadequate written descriptions of cooperating teachers' roles and responsibilities, missed opportunities to develop more fully the quality of cooperating teacher-practicum student collaborations, as well as cooperating teachers' recommendations for enhancing the practicum experiences of those involved.