This note provides guidance on how to select fiscal rules in a wide range of economies, including advanced, emerging market, and developing economies. The principles and methods discussed are intuitive and easy to implement, and leave room for policy judgment. The methods are based on past academic and IMF work, including analytic and policy papers, technical assistance missions, and training. The note is structured as follows. The first section lays out general principles regarding the design of fiscal rules. The second section reviews the most common rules and describes their pros and cons. The third section presents the various types of analytical tools used to select fiscal rules (some files and manuals accompany this note to implement the methods; they are available from the authors upon request). The last section offers some considerations on rules in developing countries, with a specific focus on commodity exporters. An overview of the theoretical literature is provided in the Appendix. This is one of two guidance notes on the design of fiscal rules; the other one focuses on rule calibration. The two exercises are linked: if a fiscal framework had to be built from scratch, rules would need to be selected and calibrated at the same time.