Sustainable design has become a key objective in modern engineering, as early design decisions largely determine a product’s environmental impact. In this context, this thesis presents a framework that enables directional disassembly through the use of topology optimization. The approach integrates geometric modeling via the level set method with numerical analysis using the eXtended Finite Element Method to design structures that can be separated along prescribed directions. A disassembly constraint is introduced through the concept of shading, which models geometric obstruction between parts in a given removal direction. Two different shading formulations are considered and validated: a distance-based method originally proposed by Allaire et al. (2023), which is adopted in this work, and an alternative gradient based formulation. Shading is computed in both cases from a heat diffusion problem, either using the difference between two generated distance fields or gradient misalignment. The former yields a more accurate shade but is more computationally expensive, whereas the latter is more efficient but prone to boundary effects. Both single-material and two-material formulations are considered. The shading formulations are subsequently used in a multi-objective topology optimization framework that incorporates perimeter penalization and level set regularization, ensuring smooth, manufacturable, and disassemblable designs. Optimization studies show that the proposed framework can generate disassemblable designs. The methodology is further extended to incorporate structural performance objectives, enabling the creation of designs that are both mechanically efficient and easily disassemblable.