A catalog of research units in Pennsylvania is presented as part of the Pennsylvania Research Inventory Project. This project focuses on research units that have a defined focus of interest, specialized professional personnel, funding or budgeted support, and distinctive products and/or outcomes. The catalog lists research units in alphabetical order by the name of the parent company or sponsoring institution. Two simplified indexes can be used to locate all research units in a particular category on the printed list. The geographical index is entered by using development regions (shown on a map), counties within each region, and units within each county. The Standard Industrial Code (SIC) and the Record ID for each entry are also shown. A second users index shows the SIC code with the description of each category. After the three digit category, all the Record IDs are listed for units engaged in research under the subject area. In addition, a list of key terms contains all the descriptive words used by survey respondents to explain their research activities. The "NCES Academic Program" section provides a detailed outline of another taxonomy used by respondents to specify their work. (SW)