This Ocean Sciences Instrumentation development project is a collaborative effort between Scripps Institution of Oceanography and Amatek Corporation, Straza Division. The project's goal is to develop, build and test a new system of hardware and software for acoustic Doppler current profiling. It will involve modifi- cations to existing Amatek Doppler speed logs that are installed on numerous commercial ships and research vessels. The new system will make use of advances in LSI chip technology, the availability of new peripheral cards and software for IBM AT compatible computers and all developed software will be access- ible to the user. Knowledge gained will be in the public domain. Amatek will provide a Doppler receiver chain module board and two digital signal processing boards. Scripps personnel will oversee software development, the selection of optimal signal processing algorithms, and preparation of documentation manuals. Acoustic Doppler Current Profilers have become important tools to derive the movement and circulation of water under a ship's path. These devices are relatively new to academic researchers, but represent a major advance in scientists' ability to study ocean circulation. Rapid advances are still being made in signal processing electronics and Doppler sonar theory and it is suggested that most research-oriented, commercial systems now available, lag behind procurable technology. Also, restricted access to hardware and software preclude the scientist from being being able to modify signal processing algorithms to make best use of available data. Successful completion of this project will further scientists' ability to use this new technology.