Defending a deposition in federal court is one of the quietest high-stakes tasks in civil litigation, because a single sworn admission can decide a case on summary judgment or reset its settlement value months before trial. This UpLaw research guide follows the defending attorney from the preparation session through the errata sheet, marking the ethical boundary between readying a witness and coaching one. It analyzes the objection regime of Federal Rule of Civil Procedure 30(c)(2), the difference between waivable form objections and preserved substance objections, and the prohibition on speaking and suggestive objections rooted in Hall v. Clifton Precision. It examines the three exhaustive grounds for instructing a witness not to answer, the split over conferring during breaks, the affirmative duty to educate a Rule 30(b)(6) designee, the defense of experts and apex executives, the Fifth Amendment in civil cases, the circuit split over substantive errata, and the mechanics of suspending an abusive deposition under Rule 30(d)(3). Invented dialogue illustrates each principle, and the guide closes with a field checklist, an FAQ, and curated cross-references.