Archaeological projects vary enormously in size, complexity, object of study, timescale and other characteristics. Therefore, finding the best possible methodology for any given project is often a difficult task, and most of the time we keep wondering whether the methodology that we are using is, in fact, the best possible one. An inadequate methodological choice can ruin many months worth of fieldwork, bias the interpretation of data, and slow down or impede cross-project comparison of results. Ideally, a methodology should be perfectly adjusted to the needs of the project; it should be based on well-proven techniques and knowledge; it should be clearly expressed so that it can be unambiguously enacted, communicated and shared; and it should be enhanced over time from the information gathered while it is applied. The approach known as method engineering has been successfully used in some disciplines to achieve these objectives. Method engineering is an approach to the crafting of methodologies that conceives a methodology not as a monolithic black box, but as an assembly of pre-existing components that are selected and composed together from a repository. Each component in the repository encapsulates a proven, reusable "atom" of knowledge with clear indications on how it should be used and combined with other components. Method components often refer to the process to be carried out (i.e. the tasks), the outcomes to generate or inputs to take into account (i.e. products), the people and teams that actually do all this (i.e. producers), and the temporal organisation of all the previous (i.e. stages). Using method engineering, the characteristics of the archaeological project at hand determine what pre-existing tasks, products, producers and stages are selected from the repository and assembled together in order to create a purpose-fit, well proven methodology that can be clearly expressed, enacted and enhanced over time, and suggests what additional method components need to be created specifically for the project. This paper offers a brief introduction to method engineering from the perspective of the humanities and social sciences, and shows how method engineering can be valuable to archaeology in particular. Some examples are given of how a sample archaeological methodology can be put together from the components in a repository. The ISO/IEC 24744 method engineering standard is used as an ontology of methodologies.