A deep gap separates theoretical and methodological development in the field of Education and Communication from its practice in healthcare centers. The dominant concept in Health Education is that there is invariably a paucity to be overcome through technical and scientific knowledge disseminated by healthcare professionals, to help patients or communities to comply with medical prescriptions and healthcare programs. In the empire of Biomedicine and medical technology, patient knowledge is increasingly disregarded. We start from a different point of view: laymen have valuable knowledge, acquired through the experiences of dealing with their own health. To identify and recognize the value of the knowledge developed by a community of people with type 2 diabetes mellitus where their self-care and self-control is concerned, we conducted an investigation of an exploratory and qualitative nature. To achieve a more suitable characterization of their knowledge, we employed the concept of competences, such as the abi lity to mobilize knowledge to control concrete situations, including both behavioral skills (knowing how to be) and know-how. Data collection relied on four focus groups and seven in-depth interviews with patients; all were recorded and their content was transcribed. We identified and classified the difficulties of living and dealing with the care of diabetes in 25 problem areas. In each one of them we assessed the competences patients developed to look after and control their diabetes themselves. The identification of these competences enabled us to obtain a preliminary record of the collective intelligence of this community where self-care of diabetes is concerned. In a second stage of this investigation, these competences will be assessed among a broader segment of this community and then processed using SEE-K® software (Knowledge Trees). Our objective is to investigate the possibility of using this tool for managing and sharing knowledge across a community. We will thus be able to advance toward an under standing of collective intelligence, not as a merging of individual intelligences into a community magma, but recognizing the value and the mutual reactivation of singularities, and the possibility of making them available in real time, as knowledge from all and for all. [Project financed by FAPESP (process 03/12970-2) and FUNDUNESP (process 0114/03)]