Electronic Data Interchange (EDI) is an important part of interorganizational electronic commerce due to the strategic impact derived from its use. In order to ensure successful implementation of EDI, EDI controls must first be developed. Because they are implemented in an environmental context, the characteristics of organizational environments have a significant impact on EDI controls. The control strategy for the EDI system - formal, informal, and automated controls - should fit certain organizational environments. A research model has been developed to depict the moderating effects of six environmental variables including industry, organizational, and task characteristics on the relationships between controls and implementation. It is shown empirically that the relationships between EDI controls and implementation are indeed affected by these factors. The results can help management design formal, informal, and automated controls in view of their own environmental contexts.