I will discuss my recent projects involving measurements and renormalization. While this talk is very preliminary, I hope to share my motivation, ultimate goals, and difficulties in the projects so that we can exchange relevant ideas. Firstly, I will discuss our approach to extend the Wilsonian (momentum-space) renormalization group to many-body systems, aiming at its generalization involving measurements. This is work in progress with Yuxuan Zhang (U Toronto). In the second part of my talk, I consider the problem of optimizing measurements in large systems. I propose a new quantity inspired from holography and present some calculation of two qubits. This is partially based on our work with Beni Yoshida (Perimeter). Finally, if time permits, I briefly discuss my project for entanglement harvesting in many-body systems, aiming at nonperturbative optimization of detectors via quantum circuit realizations and its relation to the causal structure.