This dissertation explores a new approach to construct tools in the domain of reverse engineering. The approach uses already available software components -- such as off-the-shelf components and integrated development environments -- as building blocks, combining and customizing them programmatically to realize the desired functional and non-functional requirements. This approach can be characterized as component-based tool-building, as opposed to traditional tool-building, which typically develops most of the tool's functionalities from scratch. The dissertation focuses on research tools that are constructed in a university or research lab (and then possibly evaluated in an industrial setting). Often the motivation to build a research tool is a proof-of-concept implementation. Tool-building is a necessary part of research -- but it is a costly one. Traditional approaches to tool building have resulted in tools that have a high degree of custom code and exhibit little reuse. This approach offers the most flexibility, but can be costly and can result in highly idiosyncratic tools that are difficult to use. To compensate for the drawbacks of building tools from scratch, researchers have started to reuse existing functionality, leading towards an approach that leverages components as building blocks. However, this emerging approach is pursued in an ad hoc manner reminiscent of craftsmanship rather than professional engineering. The goal of this dissertation is to advance the current state of component-based tool-building towards a more disciplined, predictable approach. To achieve this goal, the dissertation first summarizes and evaluates relevant tool-building experiences and case studies, and then distills these into practical advice in the form of lessons learned, and a process framework for tool builders to follow. The dissertation uniquely combines two areas, reverse engineering and software components. The former addresses the constructed tool's application domain, the latter forms the foundation of the tool-building approach. Since this dissertation mostly focuses on tools for reverse engineering, a thorough understanding of this application domain is necessary to elicit its requirements. This is accomplished with an in-depth literature survey, which synthesizes five major requirements. The elicited requirements are used as a yardstick for the evaluation of component-based tools and the proposed process framework. There are diverse kinds of software components that can be leveraged for component-based tool building. However, not all of these components are suitable for the proposed tool-building approach. To characterize the kinds of applicable components, the dissertation introduces a taxonomy to classify components. The taxonomy also makes it possible to reason about characteristics of components and how these characteristics affect the construction of tools. This dissertation introduces a catalog of components that are applicable for the proposed tool-building approach in the reverse engineering domain. Furthermore, it provides a detailed account of several case studies that pursue component-based tool-building. Six of these case studies represent the author's own tool-building experiences. They have been performed over a period of five years within the Adoption-Centric Reverse Engineering project at the University of Victoria. These case studies, along with relevant experiences reported by other researchers, constitute a body of valuable tool-building knowledge. This knowledge base provides the foundation for this dissertation's two most important contributions. First, it distills the various experiences -- the author's as well as others -- into ten lessons learned. The lessons cover important requirements for tools as uncovered by the literature survey. Addressing these requirements promises to result in better tools that are more likely to meet the needs of tool users. Second, the dissertation proposes a suitable process framework for component-based tool development that can be instantiated by tool builders. The process framework encodes desirable properties of a process for tool-building, while providing the necessary flexibility to account for the variations of individual tool-building projects.