At Yale since 1977, Bob Crabtree is now Whitehead Professor. In early work, he reversed homogeneous catalytic alkene hydrogenation to bring about alkane dehydrogenation. The so-called 'Crabtree catalyst' has proved useful for certain challenging cases and has therefore seen broad use. This was followed by work on complexation of molecular hydrogen to metals and finding a new type of hydrogen bonding that he called dihydrogen bonding. Recently, in collaboration with Gary Brudvig, he developed water oxidation and C-H bond conversion to C-OH with iridium catalysts in connection with the problem of green catalysis and alternative energy production. He has been American Chemical Society (ACS) and Royal Society of Chemistry (RSC) organometallic chemistry awardee, Baylor Medallist, Dow, Williams and Mond lecturer, Centenary awardee, has chaired the ACS Inorganic Division and is the author of an organometallic textbook now in its 6th edition. He is a Fellow of the ACS, RSC, and the American Academy as well as a member of the National Academy of Sciences.