The Computer Search Center (CSC) at IIT Research Institute (IITRI) provides information from computer-readable data bases to users in industry, government and universities. The center was designed to meet user needs by providing a variety of services from multiple data bases with minimal restrictions and a high degree of flexibility. A new modular machine-independent PL/1 software system was developed for handling virtually any bibliographic-type data base. CSC programs have run at nine different computer facilities with different: hardware, computer models, versions of OS, peripherals, and releases of the PL/1 compiler. All data bases are converted by preprocessors to a standard IITRI format which employs a directory and character string type of file structure. User oriented profile features include: full free form Boolean logic with any degree of nesting; search terms may be any data element on a data base; search terms may be single words, multi-word terms, phrases, or term fragments; full truncation capabilities; optional sort by author, citation number, or weight; and optional printing of output on 5 × 8 cards, multilith masters, paper, or tape. User aids were developed for each data base to assist in profile development and monitoring. They include: search manuals, truncation guides, term frequency list and KLIC indexes. Research is conducted and statistics maintained to study, monitor, and improve Center components including data bases, user satisfaction, systems, personnel functions and services. The many advantages of computerized retrieval, which are the raison d'être for the center, include: coverage, thoroughness, consistency, interdisciplinariness, recall, speed, regularity, timeliness, file preparation and cost effectiveness.