Asynchronous multimedia conferencing (AMC) can be seen as a multimedia extension of text-based computer conferencing, which is a form of group-based distance learning technology now in routine use in many places. In contrast, AMC is quite novel and raises new issues concerning usability, appropriate pedagogical methods and potential educational benefit. In this paper we report on some exploratory work whose context is set by the goal of using AMC to support continuing professional development among geographically dispersed groups of practitioners. In particular it explores ways in which AMC may enable knowledge that is tacit and embedded in working practices to be rendered into shareable forms for collaborative professional learning. The paper reports on work-in-progress on a European-funded project, SHARP (SHAreable Representations of Practice). It describes some initial requirements-oriented studies and locates this activity within the broader landscape of AMC environments used for continuing professional development. In particular it discusses issues concerned with capturing representations of practice. Using digitised videoclips to create representations of practice is a relatively unexplored approach for professional learning and this approach has surfaced issues about what is needed in order to render a practitioner's video representation into a communicable form. The paper offers a typology within which different kinds of videoclip, and different kinds of representational purposes, can be located. It sketches an AMC interchange in terms of the building up of a web of multimedia objects. Finally it offers a set of descriptors for such multimedia objects that can be useful in classifying and indexing entries in an educational AMC.