This recommended practice provides guidelines for the design, analysis, manufacture, testing, installation, and operation of flexible pipes and flexible pipe systems for onshore, subsea, and marine applications. This recommended practice supplements API Specification 17J [1] and API Specification 17K [2], which specifies minimum requirements for the design, material selection, manufacture, testing, marking, and packaging of unbonded and bonded flexible pipes respectively [3]. In general, flexible pipe is a custom-built product that can be designed and manufactured in a variety of methods. It is not the intent of this document to discourage novel or new developments in flexible pipe. On the contrary, it is recognized that a variety of designs and methods of analysis are possible. For this reason, some topics are presented in general terms to provide guidance to the user while still leaving open the possibility of using alternative approaches. The reader should be aware that flexible pipe technology (i.e., concepts, design and analysis methodologies and criteria, components manufacturing and testing, operational roles and demands, maintenance and inspection, etc.) is in a state of rapid and continuing evolution. Potential users therefore need to apply care in their application of the recommendations within this document.