26 Dermal Component–Based Optical Modeling of Skin Translucency skin is presented as multi-layered medium. The variations in spatial distribution of blood, pheomelanin, eumelanin, index of blood oxygen saturation, hematocrit, and volume fraction of water are taken into account. The developed Monte Carlo (MC)-based calculator of spectra and color of human skin is supported by Compute Unified Device Architecture (CUDA), introduced by NVIDIA Corporation, that provides acceleration of modeling up to 103 times, allowing produce the results of simulation within seconds. The calculator is based on the object-oriented programming (OOP) paradigm and available online at www. biophotonics. ac. nz. Examples of MC modeling of skin optical properties optimal for removal the tattoo or any other localized absorbing abnormality by laser thermolysis are also presented. This optimization is based on the laser wavelength selection and application of immersion optical clearing for enhancement of laser light selective absorption.