This document specifies an extension to the Geospatial API for Features Part 1: Core standard that defines the behavior of a server that supports the ability to present geometry valued properties in a response document in one from a list of supported Coordinates Reference Systems (CRS). Each supported CRS is specified by reference using a uniform resource identifier (URI). This document specifies: How, for each offered feature collection, a server advertises the list of supported CRS identifiers; How the coordinates of geometry valued feature properties can be accessed in one of the supported CRSs; How features can be accessed from the server using a bounding box specified in one of the supported CRSs; and How a server can declare the coordinate reference system used to present feature resources.