Experience with a minicomputer based field-portable vibration analysis system has been gained on several projects including a five story office building, a nuclear power plant containment and internal piping system, and an offshore oil platform. The purpose of the system is to acquire data on up to 64 channels and provide for the organization, documentation, and presentation of the reduced data. Modal parameter identification software is also available. To date the system has proven to be a valuable extension of previous field testing methods. This paper reviews the system's design and its performance in several field tests.