The material and product accuracy limitations of rapid prototyped products can often prevent the use of rapid prototyping (RP) processes for production of final end-use products. Conventional machining processes are well-developed technologies with the capability of employing a wide range of materials in the creation of highly accurate components. This paper presents an overview of how conventional machining processes can be used for RP and direct manufacturing processes. The methodologies of computer numerical control machining for rapid prototyping (CNC-RP) and wire electronic discharge machining for rapid prototyping (WEDM-RP) are presented in this paper. A general discussion of selection criteria and cost comparisons among both current additive RP and conventional machining approaches to rapid manufacturing are also presented.