Most economic impact studies are prepared by external consultants at significant cost to an individual college, a higher education state system, or a set of institutions with similar Carnegie Classifications. This case study provides a detailed framework that academic institutions may use to derive economic impact estimates without hiring external consultants. This research is unique in its case study analysis of the collective impact of five colleges that differ with respect to Carnegie Classification, control type, enrollment size, and selectivity. Utilizing internal expertise and resources, the schools estimate they contributed $923 million to $1.2 billion to the Berks County, Pennsylvania economy in 2004-05. Detailed discussion of the underlying methodology, data sources, multipliers, professional expertise needs, and case study limitations are provided. (Contains 4 tables.)