DataFrame and DataSource (or similar ADO.NET constructs) are indeed of completely different types, so a direct assignment would not work (in fact not compile, I hope). Explicit conversion ("cast", operator= overload) would require to be very sure of the behavior in all cases. I suspect there are many cases where users would expect different behaviors. So, aside from being quite a bit of work, I am not convinced the desirable conversion behavior can be clearly defined such that R.NET can offer a reliable "black box" implementation of the conversion. Some helper functions for part of the conversion to data frames may be provided, but this will depend on contributors...