Aims and objectives: To explore the nature of knowledge exchange on a multi-disciplinary Australasian intensive care virtual community of practice, “ICUConnect.”. Background: Current organisational structures and cultures constrain the social networks of healthcare professionals, limiting access to contemporary best practice knowledge. While virtual communities can facilitate knowledge and clinical expertise exchange in professional networks, their effectiveness has not been established. Design: A sequential mixed-methods design with a quantitative core and qualitative supplementary component was used to explore the content of discussions from an intensive care virtual community. SRQR has been used to report this study. Methods: Email archives of an intensive care listserv (2003–2013) were mined using a two-stage sampling technique to identify discussion threads (with >2 posts) concerning ventilator or airway practices (cluster) and two sets of 20 threads (stratified across years). Summative content analysis was used to examine both manifest and latent content. Results: Forty threads containing 326 emails posted by 133 individuals from 80 organisations were analysed. Nurses contributed 68% (55% were in clinical leadership roles) and physicians 27%. Three subject areas were identified: clinical practices (71%); equipment (23%); and clinical governance (6%). “Knowledge-requested” and “knowledge-supplied” posts were categorised as follows: experiential and explicit (33% and 16%, respectively); experiential (27% and 35%); or explicit (40% and 17%). Knowledge supplied was also categorised as “know-how” (20%); “know-why” (5%) or “no knowledge” exchanged (6%). The central construct of virtual community work was identified with six elements that facilitated participation and knowledge exchange including: (a) the discussion thread; (b) sharing of artefacts; (c) community; (d) cordiality; (e) maven work; and (f) promotion of the VC. Members asked questions to benchmark their practice, while those who answered were focused on ensuring that best practices were delivered. Conclusions: ICUConnect reflected characteristics of a virtual community of practice, enabling key benefits for members and the broader Australasian intensive care community, especially access to best practice knowledge from clinical experts. Relevance to clinical practice: This study demonstrated that a practice-based VC can function effectively as a VCoP to establish an effective professional network where members have access to up-to-date best practice knowledge. Healthcare organisations could leverage VCs to support the professional development of HCPs and ensure that local clinical practices are based on contemporaneous knowledge. Participation by nurses in these communities facilitates individual professional development and access to important clinical knowledge and expertise, and ultimately reinforcing the unique position of nursing in delivering effective, consistent high-quality patient care.