["Journal of Engineering Education, Volume 115, Issue 2, April 2026. ", "\nAbstract\n\nBackground\nThe need for interdisciplinary training is increasingly important, but assessing the effects of interdisciplinary education initiatives remains challenging. One of the leading difficulties is identifying and selecting the best instrument or technique for a given purpose.\n\n\nPurpose\nTo help researchers and educators identify available options and determine the best options for their purposes, we conducted a literature review and created a heuristic table of available techniques. Our review addresses the questions: (1) What domain‐general techniques and instruments exist for assessing interdisciplinary learning or knowledge? (2) What research scenarios, populations, and questions are each technique or instrument most applicable to?\n\n\nScope/Methods\nWe systematically conducted a state‐of‐the‐art review to identify relevant tools for assessing aspects of interdisciplinary knowledge or learning outcomes. A total of 2435 documents were identified in ERIC and Web of Science, and their titles and abstracts were screened using five inclusion criteria. This was supplemented by snowball searching and hand searching.\n\n\nResults\nTwenty‐nine studies published between 2000 and January 2025 were included in the final analysis. The dataset is primarily from the United States and based on undergraduate student populations in Science, Technology, Engineering, and Math (STEM) contexts. It is nearly equally split between quantitative and qualitative data sources.\n\n\nConclusions\nAssessing interdisciplinary learning remains the “black hole” that Boix Mansilla described in 2005. Advancements in interdisciplinary training for engineers will require greater attention to assessing learning and knowledge in order to understand the impacts and outcomes of such training. We offer recommendations for researchers and educators to advance assessment of interdisciplinary learning.\n\n"]