There are multiple definitions and understandings of the case study. According to Bromley (1990), it is a ‘systematic inquiry into an event or a set of related events which aims to describe and explain the phenomenon of interest’ (p. 302). The unit of analysis can vary from an individual to a corporation. While there is utility in applying this method retrospectively, it is most often used prospectively. Data come largely from documentation, archival records, interviews, direct observations, participant observation and physical artifacts (Yin, 1994).