There is continuing interest in the relationship between knowledge and practice in social work. Overly narrow conceptualizations of the EBP model deepened the gap between practice knowledge and formal research evidence in the profession. While much has been written about the dissemination and adaptation of research findings to practice, much less is known about the actual sources of knowledge social workers draw on in their practice. This paper reports findings from an exploratory survey about the sources and content of knowledge that changed professional practice among social work field instructors (n=250) in St. Louis. An analysis of open-ended responses revealed that coworkers and continuing education programs are the most important sources for knowledge and information that influence practice. While academic journals are perceived by practitioners to be relatively unimportant sources for such knowledge, research findings on the background and effectiveness of interventions, make up the primary content that appears to affect social work practice. The findings suggest that formal research knowledge is important but that it is primarily accessed through professional networks and training programs instead of directly from peer-reviewed journals. Social media platforms seemed to be insignificant sources for professional knowledge. These insights raise important questions about how social workers use social media and the role of occupational networks and associations for the dissemination of research findings. Finally, our findings suggest that agencies and researchers think more purposefully about the infusion of knowledge into practice through opportunities for professional socialization, the use of research briefs, and open-access, peer-reviewed journals.