Because of the lack of tools available to assess problem-solving skills, teachers often revert to more traditional instructional approaches (e.g. lecture-based, memorization) that fail to prepare learners for the complexity of dynamic work environments. To overcome this challenge, technology solutions are needed that accurately and efficiently assess complex problem-solving skills such as causal reasoning. Moreover, these tools must be valid and reliable so instructors can accurately assess student learning. This emergent report details the design and development of Incremental Thesaurus for Assessing Causal Maps. As will be described, the software offers three unique features: (a) analysis of causal map with little or no manipulation of the original file; (b) a growing repository of terms that supports efficient assessment and (c) ability to codify the level of concept complexity using the structure–behavior–function framework.