Maxwell’s demon is gedankenexperiment where a hypothetical being capable of acquiring all microscopic information about a system, is able to act based upon it in order to extract work without apparent energy expenditure, thus seemingly violating the second law of thermodynamics. This provocative thought experiment has long inspired investigations at the intersection of information theory and thermodynamics. In the quantum domain, where information acquisition is constrained by measurement invasiveness and resource finiteness, this concept becomes even more subtle and interesting. In this seminar, I will introduce a quantum Maxwell’s demon operating under partial information and finite resources who estimates a system’s state using a limited number of projective measurements and extracts work via an ergotropic unitary transformation. We show that although limited information generally reduces extractable work, carefully aligning the measurement strategy with thermodynamically relevant observables can lead to a higher efficiency than full quantum state tomography. These findings offer new perspectives for optimizing work extraction in quantum devices operating within Hilbert spaces of large dimension and under realistic constraints.