Baker has authored or co-authored more than 1000 scientific contributions, including 18 books, 400 research articles and chapters, more than 485 abstracts and short research reports (nearly all of them associated with papers that were presented at professional meetings, conferences, and workshops), 34 extended technical reports; 42 encyclopedia articles; 39 published book reviews; plus guidebook contributions and various other writings, including popular works in science. His research has concerned paleoflood hydrology (a field of study that he defined in the 1970s and 1980s); flood geomorphology; channels, valleys, and geomorphic features on Mars and Venus; catastrophic Pleistocene megaflooding in the northwestern U.S. and central Asia; history/philosophy of Earth and planetary sciences; and the interface of environmental science with public policy. Professor Baker has been President of the Geological Society of America (1998), Chair of the American Association for the Advancement of Science Section on Geology and Geography (1992-93 and 2008-2009), and President of the International Union for Quaternary Research Commission on Global Continental Paleohydrology (1995-99).