It is our pleasure to present the papers from the 20th International Workshop on Languages and Compilers for Parallel Computing For the past 19 years, this workshop has been one of the primary venues for presenting and learning about a wide rangeof currentresearchin parallelcomputing. We believe that tradition has continued in this, the 20th year of the workshop. This year, we received 49 paper submissions from 10 countries. About a quarter of the papers (12 out of 49) included authors from industry. We selected 23 papers to be presented at the workshop, for an acceptancerate of 47%, which...