Federal employee unions are battling executive agencies in several negotiability cases pending before the Federal Labor Relations Authority. These cases raise a web of constitutional and legal issues about the Government's right to test employees on a random basis. The cases will turn decisively on the interpretation of whether Federal drug testing guidelines are Government-wide regulations. If they are so viewed, then bargaining seems prescribed. If not, then the Authority must balance the reserved rights of management against the right of unions to bring forth proposals rgarding procedures and arrangements. The Authority could support management's side by declaring that proposals contravened Government-wide regulations or invaded a reserved managerial right. It could rule that Office of Personnel Management and Health and Human Services promulgations were guidance and therefore negotiable; or, it could take an intermediate position, holding some proposals (e.g., probable cause testing) are nonnegotiable, while others are procedural and hence negotiable. The outcome of these cases will have implications both for drug testing policies and for labor relations. 31 notes.