The purpose of this qualitative case study was to investigate the different methods in which electronic portfolio support staff acquired their expertise. In this study, five electronic portfolio support staff members served as a purposeful sample for analysis. Data were gathered over the course of one semester using individual and group observations, interviews with each study participants, demographic information, narrative prompts, and concept maps. Data were collected from each of the data sources and analyzed using NVIVO 8. Data were then categorized into thirteen different behavioral categories of expertise taken based on the literature. Further analysis revealed four predominant themes of expertise that were observed from each research participant: (a) domain knowledge, (b) performance, (c) problem solving, (d) deliberate practice in the domain over time, and (e) participation in a learning community. Next, a cross-case analysis was used to study the similarities and differences in the experience of each study participant in their journey to acquire electronic portfolio expertise and knowledge. Findings from the within and across case studies indicated that direct experience with the electronic portfolio was a major contributor of acquisition of expertise for each of the research participants. Domain performance tended to improve as the electronic portfolio support staff member acquired more domain experience through deliberate practice over time. Findings also indicated that problem solving skills improved through direct interaction with the electronic portfolio and through observation of more advanced electronic portfolio support staff members. Within the context of a learning community, the factors of domain knowledge, performance, problem solving, deliberate practice over time, and preservice teacher relationships interacted with one another in producing electronic portfolio expertise.