Much has been written about the rule that prevents the use of evidence obtained in violation of the Fourth Amendment’s prohibition against unreasonable search and seizure. The quantity of the literature, however, threatens to obscure important areas of emerging agreement. This paper, part of a symposium in the Ohio State Journal of Criminal Law to appear for the 100th anniversary of Weeks v. United States, presents seven theses. The first four enjoy widespread support, with considerable justification: 1) the exclusionary rule is not constitutionally required; 2) history does not resolve the propriety of the exclusionary rule; 3) the Fourth Amendment requires an effective deterrent to unreasonable search and seizure; and 4) the exclusionary rule offers some meaningful deterrence of unreasonable search and seizure because of the political costs of exclusion. Although the remaining theses are somewhat more controversial, the general acceptance of the first four and, in particular, the recognition that exclusionary imposes political rather than economic costs, I will contend, powerfully suggests the soundness of the final three: 5) exclusion of evidence obtained in violation of the Fourth Amendment is not invariably required to preserve its deterrent efficacy; 6) exclusion is sometimes required to achieve constitutionally sufficient deterrence even in the absence of culpable misconduct; and 7) alternatives to exclusion are of uncertain efficacy because they rest on problematic theories of deterrence. Collectively, the seven theses amount to a grudging defense of the exclusionary rule. The exclusionary rule has many defects, but there are great difficulties identifying a superior alternative.