There is growing interest in the nature and scale of scientific collaboration regarding the processes involved with knowledge creation and sharing. One of the possible approaches to developing metrics for this area of research is based on the idea that co-authorship creates a social network of researchers. We present an exploratory study using a social network approach to examine the structure and pattern of knowledge creation and sharing within a Portuguese research community, working in the agricultural field, over the last seven years. The members of this community are with the Instituto Nacional da Investigacao Agraria (INIA) which recently became part of a newly created R&D State Laboratory, Instituto Nacional dos Recursos Biologicos (INRB), under the umbrella of the Portuguese Ministry of Agriculture Rural Development and Fisheries. The social network analysis used data from an information system containing the results from all the scientific activities developed in the last seven years by the research community working in INIA. The information system was the major result of AGRO 444 - Development of an Information System for Knowledge and Innovation Discovery and Diffusion in the Agro-Rural Sector, a project funded by Measure 8.1 of Programa AGRO, one of the policy instruments of "3 degrees Quadro Comunitario de Apoio" (Third European Framework Aid to Portugal, 2000-2006). From this data, a knowledge network was developed based on co-authorship patterns extracted from the information system, covering the period 2000-2006. This knowledge network supported the analysis of specific paths through which knowledge sharing occurred and by which knowledge capital was nurtured within the agricultural R&D activities of this institution.