The 3rd edition of the Programming and Tuning Massively Parallel Systems summer school (PUMPS) has started sucessfully with around 100 international participants. Its aim is to enrich the skills of researchers, graduate students and teachers with cutting-edge technique and hands-on experience in developing applications for many-core processors with massively parallel computing resources like GPU accelerators. More information on page http://bcw.ac.upc.edu/PUMPS2012/