This article presents an overview of ten specific problems and considerations that are typically involved in designs of bibliometric indicators for national performance-based research funding systems (PRFS). While any such system must be understood and respected on the background of different national contexts, mutual learning across countries can inspire improvements. The paper is partly based on experiences from a Mutual Learning Exercise (MLE) on Performance Based Funding Systems which was organized by the European Commission in 2016–17and involved fourteen European countries, partly on experiences from advising a few other countries in developing such systems. A framework for understanding country differences in the design of PRFS is presented first, followed by a presentation of the five specific problems and considerations that are typically involved in designs of bibliometric indicators for such system. The article concludes with an overview of how Norway’s PRFS has dealt with the same five problems.