A common concern articulated by clinical nurse specialists (CNSs) is role confusion or ambiguity. Role confusion may lead to frustration, hamper collaboration, contribute to conflict, prevent the CNS from optimizing knowledge and skills, and even result in deletion of the position. Factors influencing the delineation of the role include the changing needs and goals of patients, families, interdisciplinary team members, healthcare institutions, and the community as well as the knowledge, skills and experience of the CNS. Clarification of the role requires identification of and insight into the specialty setting and the needs to be addressed. CNSs need to describe their role to other nurses considering an advanced practice role, to nursing educators preparing nurses to assume such roles, to administrators trying to make informed comparisons, and to the public seeking to meet healthcare needs.