The Mammalian DNA Repair Gordon Research Conference has met biannually since 1986 and covers recent highlights in research from DNA repair and related areas. The conference is known for its friendly and informal atmosphere and provides ample opportunities for informal discussions among students, postdocs, PIs and researchers from industry. DNA repair processes are essential for preventing carcinogenesis in humans, as evidenced by a large number of cancer-prone hereditary disorders resulting form defects in DNA repair genes. Conversely, DNA repair proteins are increasingly sought after drug targets in antitumor therapy, as evidenced by the recent success of PARP inhibitors. The 2015 conference will feature recent highlights from all areas of DNA repair and a number of cutting edge topics, such as single molecule and structural approaches to study damage recognition, the emerging area of ribonucleotide repair, non-coding RNAs in the DNA damage response, the connection of DNA repair defects with inflammation and infectious disease or the role of DNA repair enzymes in epigenetic regulation. There will also be a session of how DNA repair can be targeted for cancer therapy. Presentation of unpublished results will be strongly emphasized in instructions to all speakers, and interactive discussions involving all conferees will be actively encouraged. The conference will involve a number of development opportunities for students, postdocs and early career scientists, including the possibility to submit abstracts for short talks, activities to foster social interaction between PIs and junior researchers, and the possibility to attend the associated Gordon Research Seminar. This conference has frequently been over-subscribed in the past, so early application with submission of abstracts is strongly encouraged to aid in selection of conference participants and short platform talks. We look forward to your active participation at the 2015 Mammalian DNA Repair GRC in Ventura!