Laser sintering is a form of additive manufacturing in which objects are created by selectively fusing together successive layers of powdered material (1). This presents a completely new and diverse way to process polymers, with the ability to manufacture parts with great complexity in shape, and without the need for mold tooling. This enables low volume production and even completely customized products, with applications in the medical sector, fit-to-body arrangements and various consumer markets. The widely acknowledged stumbling block in the progression of laser sintering is the limited range of materials, in particular polymers, which can currently be processed successfully by this technique (2). At present, the market is dominated by a few polyamide-12 grades. In order to broaden the application window of laser sintering, an increase in the number and variety of laser sinterable materials is required. Therefore, a fundamental understanding of all material properties in relation to the process parameters is required. In this study, the behavior of the benchmark PA-12 is thoroughly investigated and the key material parameters that allow proper sintering are identified. This includes a thorough investigation of powder flow, coalescence and rheology in the melt, as well as a study of the thermal transitions. From this work, several strategies arise to find new materials for sintering, with a focus on materials with specific crystallization and rheological behavior. REFERENCES 1. C.R. Deckard, “Selective laser sintering”, Ph.D. Thesis, University of Texas at Austin, 1988. 2. R.D. Goodridge, C.J. Tuck, R.J.M. Hague, Progress in Materials Science 57, 229-267 (2012)