ABSTRACT
Identification is the first step towards determining whether the occurrence of business clusters is changing and in evaluating the value of efforts to promote cluster formation. To date, no agreed method for identifying and mapping the distribution of clusters has been developed. Even strong advocates of the importance of clusters acknowledge that there are obstacles to any comprehensive and rigorous identification. It is noted frequently, for example, that cluster participants may not fit the categories identified in official statistics and that this risks even potentially large clusters being unrecognized. Such an instance has been claimed with a concentration of more than 400 medical-device companies, encompassing perhaps 40,000 jobs in Massachusetts (Porter 1998:79). Official employment data allocated this activity among diverse industries. Once revealed, executives reportedly came together to work on issues of mutual interest, creating a strong cluster.
