Adaptive problem solving denotes the ability to achieve one’s own goals in a dynamic situation in which a method for reaching a solution is not directly available. Cognitive and metacognitive processes are necessary to define the problem in diverse environments and contexts, to search for information, and to implement the solution. This domain and the corresponding instrument were newly developed for PIAAC Cycle 2 and constitute an important innovation. The assessment tasks are embedded in everyday scenarios within an interactive environment. Possible tasks in this domain may include organizing trips or celebrations in coordination with other (virtual) persons, or planning, controlling, and monitoring systems (e.g., production machines or plants).