The communication of corporate environmental messages has a history of mixed results, and concerns are mounting around the possibility of information overload, and the quality and accurateness of the content. In this research I look at the complexities associated with environmental information and communication, and explore the relationship of information complexity and credibility as key constructs that influence communication performance. Recent emphasis on Life Cycle Assessment (LCA) information is presented as holding some promise to improve the effectiveness of environmental claims. Results indicate that although the likelihood that more complex communications in an advertising context makes for poor advertising; the credibility gained through more explicit environmental disclosures, favorably influences the perceptions toward the company and the brand.In a second study with architects, I found that, advertisements with environmental messages are more effective than those presenting functional product benefits alone, but only when the messages are substantiated with quantitative and disaggregated information [resulting from LCA studies].