Combined school and public libraries have been studied extensively for more than thirty years. Common advantages and disadvantages, together with typical problems, have been identified. From the work of researchers in three countries, predictors of success can be articulated: the population served is less than 10,000; a formal planning process involving the stakeholders was undertaken; a written legal agreement for governance, administration, finances, and operations includes guidelines for evaluation and dissolution; a decision-making board or management committee develops policies and procedures and engages and evaluates the director; an integrated facility is conveniently and visibly located, accommodating a variety of groups and resources with a separate area for adults and designated parking; the library is connected with a larger network, regional system, or consortia; the principal has a strong desire for success and teachers support the concept; one highly motivated professional librarian is in charge; there is regular communication and planned cooperation between public library and school staffs; and there are no restrictions on access to resources or on the circulation of materials