Community Health Workers (CHWs) are central to Primary Health Care initiatives, serving the essential function of extending access to health services in rural communities. In 1997, the Guatemalan government implemented the Sistema Integral de Atencion en Salud (Integrated Health Care System) (SIAS). Central to SIAS is the guardian de salud (health guardian), a CHW whose role is to refer individuals in their communities to higher levels of care. SIAS is highly effective in recruiting guardianes (guardians), with over 25,000 in 2003. Yet, there are several types of established CHWs throughout Guatemala with different training and abilities. The presence of existing CHWs, particularly the promotor de salud (health promoter) which specializes in curative services, strongly influences participation in new programs as they set local expectations of the position. In this paper, I analyze the implementation of the guardian in the municipality of San Martin Jilotepeque, focusing on how expectations of the position influence participation as well as how CHWs negotiate their practices in relation to these two models. I argue that differences in the ability to provide curative medicine effectively reinforces a dualistic model of CHW in rural Guatemala, creating conflict between established CHWs and SIAS guardianes de salud.