Defendants in criminal proceedings increasingly become involved in simultaneous civil litigation. The opposing party in the civil action may be a government agency or a private litigant. In addition to criminal sanctions, defendants in parallel civil proceedings face a broad spectrum of sanctions, including restitution, remediation, fines, forfeiture, and loss of government benefits and privileges. Issues raised by parallel civil and criminal proceedings include conflicts between the disparate scopes of civil and criminal discovery and problems concerning the disclosure of grand jury materials. Moreover, concurrent proceedings raise constitutional questions that involve double jeopardy, the Excessive Fines Clause, and collateral estoppel. This review discusses each of the issues in detail. In a general comment, the author notes that in determining whether or not to permit concurrent civil and criminal actions, most courts have sought to balance society's interest in swift resolution of both criminal and civil disputes against any possible prejudice to either party stemming from parallel proceedings. Courts have remedied problematic cases by imposing protective orders and stays when necessary. 310 footnotes