Whenever you are asked if you can do a job, tell 'em, 'Certainly I can!' Then get busy and find out how to do it.

We searched Theodore Roosevelt's collected works, including the multi-volume *The Works of Theodore Roosevelt*, his published correspondence, and the archival holdings associated with the Theodore Roosevelt Center and the Library of Congress, and found no instance of this exact wording in any speech, essay, letter, or interview attributed to him. A full-text pass through digitized books credited to Roosevelt likewise turned up no verbatim match, though we treat that as inconclusive given the well-known coverage gaps in older speeches and letters. A live book-database search surfaced this phrasing only in recent business and self-help titles — such as *Winning in a Man's World* (2008), *Stuff I Wish I'd Known When I Started Working* (2014), and *How to Work for Yourself* (2020) — none of which predate Roosevelt or claim a different named originator, so they establish no competing source. The line circulates heavily under Roosevelt's name on quote-collection sites, but its colloquial register ("tell 'em," "get busy") sits awkwardly against his generally more formal prose, and none of those sites cites a primary text. We found no credible scholarly disagreement proposing an alternative author and no documented earlier appearance, so neither "disputed" nor "misattributed" is warranted under our policy; the absence of a Roosevelt source is not, by itself, evidence that someone else wrote it. On the balance of what we could and could not confirm, this quotation is commonly credited to Theodore Roosevelt but rests on widespread association rather than any traceable primary source: attributed.