One of the early tasks of the National Commission on Libraries and Information Science (NCLIS) was to identify the sources of public funds available for use in financing public libraries. Information is available on the amounts of federal and state funds for financing public library services. What is not known at the national level is the various revenue sources either used or available to libraries operated at the local level for the funding of their operations. The task of collecting useful data on income sources for the over 7,000 public libraries and library systems throughout the country is a formidable task. If, however, the problem is approached on a systematic basis, then the prospects for collecting such data are encouraging. This study endeavors to develop a method to accomplish that goal. The primary purpose of this feasibility study was to develop recommendations which the NCLIS could use in conducting a comprehensive study of funding sources for public libraries. (Author/SJ)