API Recommended Practice 17H provides recommendations for development and design of remotely operated subsea tools and interfaces on subsea production systems to maximize the potential of standardizing equipment and design principles. This document does not cover manned intervention@ internal wellbore intervention@ internal flowline inspection@ tree running and tree running equipment. However@ all the related subsea ROV/ROT/AUV interfaces are covered by this standard. It is applicable to the selection@ design and operation of ROTs@ ROVs and AUVs including ROV tooling@ hereafter defined as ??subsea intervention systems??. This Recommended Practice (RP) provides functional requirements and guidelines for ROV/ROT/AUV interfaces in subsea production fields for the petroleum and natural gas industries. It is applicable to both the selection and use of ROV/ROT/AUV interfaces related to subsea production equipment and provides guidance on design as well as the operational requirements for maximizing the potential of standardized equipment and design principles. This RP identifies the issues to be considered when designing for ROV/ROT/AUV operations to interact with (or near) subsea production systems. The framework and specifications set out enables the user (whether they may be on the ROV/ROT/AUV side or production facility side) to design the appropriate interface for a specific application. These interfaces include subsea docking@ recharging@ data transfer@ data harvesting@ and mechanical intervention. It is anticipated that in the future@ resident ROVs/AUVs near the seabed can provide high value for oil and gas inspection@ monitoring@ and maintenance and repair activities. The benefits of employing ROVs/AUVs in such situations include reduced operating costs and improved safety. The guidelines established in this RP leads to efficient development and deployment of ROV/ROT/AUV systems@ providing clarity for operators@ contractors@ and developers. Recommendations have been provided in a flexible manner to accommodate a wide variation of AUV styles and applications@ while maintaining an appropriate level of interface commonality for specification. This document defines four major categories of hot stabs and describes the geometry to maintain compatibility across all manufacturers. The categories were first introduced in Technical Report 17TR15 which described several common or previously used hydraulic hot stab and receptacle configurations. The approach is to ensure backward compatibility of the hot stabs described in API Recommended Practice 17H@ 2nd Edition and to align API RP 17H with API S53 and API 16D. This RP is not intended to replace sound engineering judgment as to when and where its provisions are to be used. Users need to be aware that additional or differing details may be required to meet a specific service or local legislation. This document is not intended to deter the development of new technology. The intention is to facilitate and complement the decision processes@ and the responsible engineer is encouraged to review standard interfaces and re-use intervention tooling in the interests of minimizing life-cycle costs and increasing the use of proven interfaces.