This paper reports on the use of action research in a case study involving two iterations of an online workshop implemented at two universities in late 2007 and early 2009 to prepare teaching staff for using wikis for student group work and assessment. Workshop participants were immersed in the experience of collaborating in a wiki as learners and then reflected on this experience as teachers. Experience of the pilot workshop suggested a need for more orientation, potentially by introducing a blended learning design. The second iteration highlighted a need to develop the orientation session further and increase support strategies throughout the workshop, suggesting the value of offering it at faculty or department level if no "reward" is available for participation. Outcomes from the two cycles illustrate the value of action research for iterative improvement of this staff development model and for implementing the scholarship of teaching and learning to develop and share professional knowledge in this emerging area. This paper outlines a staff development approach involving Web 2.0 applications on which others can build. (Contains 2 figures and 3 tables.)