In this thesis, we present an experimental programming support system which includes a processor for program design language(PDL) and a syntax directed editor (SDE) as key components. This system, designated as COde DESIGNER(CODESIGNER), is a prototype that allows a high level of abstraction in conceptualizing a program, supports top-down program development, and encourages good documentation during the program implementation. Close attentions are placed on the use of database as its central repository of information and the ease of extention also.