Iridium-catalyzed direct ortho C-H amidation of arenes has been shown to work well with sulfonyl- and aryl azides as the nitrogen source. The reaction proceeds efficiently with a broad range of substrates bearing conventional directing groups with excellent functional group compatibility under mild conditions. In addition, substrates forming not only 5- but also 6-membered iridacycle intermediates undergo the C-H amidation with high selectivity.