Altin, PaulChow, JongMansell, GeorgiaMcClelland, DavidMcManus, DavidNguyen, ThanhRabeling, DavidScott, Susan M.Shaddock, DanielSlagmolen, BramWade, AndrewWard, RobertYap, Min JetAbbott, B.Abbott, RobertAbbott, T. D.Adhikari, RanaBerger, B. K.Bork, R.Onken, ChristopherScalzo, RichardSchmidt, BrianWolf, ChristianYuan, FangBallmer, StefanBulten, H. J.Buonanno, R.Chua, S. S. Y.2018-11-292018-11-290067-0049http://hdl.handle.net/1885/152675This Supplement provides supporting material for Abbott et al. (2016a). We briefly summarize past electromagnetic (EM) follow-up efforts as well as the organization and policy of the current EM follow-up program. We compare the four probability sky maps produced for the gravitational-wave transient GW150914, and provide additional details of the EM follow-up observations that were performed in the different bands.application/pdf201610.3847/0067-0049/225/1/82018-11-29