Singular perturbation problems arise in various fields of engineering and science such as fluid dynamics, elasticity, quantum mechanics, electrical networks, chemical reactor-theory, bio-chemical kinetics, gas porous electrodes theory, aerodynamics, plasma dynamics, oceanography, diffraction theory, reaction- diffusion process and many other areas. If we apply the existing standard numerical methods for solving these problems, large oscillations may arise and pollute the solutions in the entire interval because of the boundary layer behavior. Thus more efficient and simpler computational techniques are required to solve singularly perturbed two-point boundary value problems. In this book, we have proposed and illustrated some simple and efficient computational methods for solving singularly perturbed two-point boundary value problems, singularly perturbed delay differential equations and singularly perturbed singular boundary value problems.