Knowledge acquisition has been identified as the bottleneck for knowledge engineering. One of the reasons is the lack of an integrated methodology that is able to provide tools and guidelines for the elicitation of knowledge as well as the verification and validation of the system developed. Although methods that address this issue have been proposed, they only loosely relate knowledge acquisition to the remaining part of the software development life cycle. To alleviate this problem, we have developed a framework in which knowledge acquisition is integrated with system specification to facilitate the verification, validation, and testing of the prototypes as well as the final implementation. To support the framework, we have developed a knowledge acquisition tool, TAME. It provides an integrated environment to acquire and generate specification about the functionality and behavior of the system, and representation of the domain knowledge and domain heuristics. The tool and the framework, together, can thus enhance the verification, validation, and the maintenance of expert systems through their life cycles.