This paper introduces a toolkit that allows programmers with no linguistic knowledge to rapidly develop a Spoken Language User Interface (SLUI) for various applications. The applications may vary from web-based e-commerce to the control of domestic appliances. Using the SLUI Toolkit, a programmer is able to create a system that incorporates Natural Language Processing (NLP), complex syntactic parsing, and semantic understanding. The system has been tested using ten human evaluators in a specific domain of a web based e-commerce application. The evaluators have overwhelmingly endorsed the ease of use and applicability of the tool kit in rapid development of speech and natural language processing interfaces for this domain.