This working document describes a stateless data transmission protocol which can be used to access a wide variety of earth sciences data. The protocol is referred to as the Data Access Protocol in much of this document and it is intended to be used in the construction of system software, particularly for the Distributed Oceanographic Data System. This protocol for data access is flexible enough to access all the data sets which will be part of the system. However, it does not offer the rich features found in interfaces intended for user-program construction. In addition to presenting the requirements and a design for the interface, the rationale for choosing this type of interface is also given. This document is written for people interested in implementing software that will be part of or work in parallel with the Distributed Oceanographic Data System.