The NPAC kernel runtime, developed in the PCRC Parallel Compiler Runtime Consortium project, is a runtime library with special support for the High Performance Fortran data model. It provides array descriptors for a generalized class of HPF-like distributed arrays, support for parallel access to their elements, and a rich library of collective communication and arithmetic operations for manipulating these arrays. The library has been successfully used as a component in experimental HPF translation systems. With prospects for early appearance of fully-featured, e cient HPF compilers looking questionable, we discuss a class of more easily implementable data-parallel language extensions that preserve many of the attractive features of HPF, while providing the programmer with direct access to runtime libraries such as the NPAC PCRC kernel.