A set of primitive operations on tuples is derived; it is shown that these operations are necessary and sufficient for the implementation tion of any language equivalent in power to the relational algebra. The translation of queries from a variety of relational languages into these tuple operations is discussed and illustrated with several examples. A method is given for the conversion of such a translated query into a network of processes and files. An optimization algorithm which operates on this network is described and demonstrated. Using this method, many different relational languages can be implemented using the same data management software; furthermore, the underlying software can be changed without requiring any changes at the user interface. This approach should yield great benefits in reduced cost and increased flexibility of implementation.