A strategy of compliance in which enforcement agents rely on negotiation is identified as a characteristic feature of water pollution control work. The strategy arises from the nature of the conduct and activities subject to regulation and from the need to maintain a continuing relationship with the regulated. In securing compliance regulatory agents shape their enforcement tactics by reference to assumptions held as to why polluters fail to comply. Bargaining is central to compliance strategy, but if a conciliatory approach fails, a more threatening posture will be taken in which a variety of mores, including bluffs about legal sanctions, may be employed. Law enforcement is treated as a matter of compliance as well as compulsion.