Collective case study involves more than one case, which may or may not be physically colocated with other cases. A collective case study may be conducted at one site (e.g., a school, hospital, or university) by examining a number of different departments or other units at that one site. Each unit is studied as part of a collection, regardless of whether the units themselves are located at single or multiple sites. The term collective case study is sometimes referred to as multi-site case study or multi-site study .
