In the previous article a brief overview on Selective Laser Sintering technique was presented and placed among other 3DP approaches. Now the time has come to dig down into the details of the SLS and unveil its phenomena. You can be confused on how exactly the laser sinters the powder, why we utilise elevated temperature or even why we can use one powdered materials and others not. This article will bring answers to those questions. We will also show the perspectives for research in terms of the SLS process and used powders.