Ripeness is a justiciability doctrine that prevents federal courts from ruling on claims before a genuine dispute has concretely materialized. Courts ask whether the hardship of withholding review outweighs the benefit of waiting for the legal issues to fully develop. In administrative law, ripeness often requires that an agency take a final action before a challenge can proceed — meaning courts may refuse to act on a challenge to a policy before the government has actually implemented it in a way that injures the plaintiff.