New York--Ben Isaacson, executive director of the Association for Interactive Marketing, a division of the Direct Marketing Association, resigned Wednesday. Isaacson said he will start his own e-mail marketing consultancy. "I'll mostly focus on e-mail marketing and implementing best practices," Isaacson said. He said he would also help companies "navigate the waters of uncertainty" in legislative matters affecting direct and e-mail marketing. The DMA is currently searching for a replacement. Isaacson's last day will be Sept. 13, but he will continue to consult with AIM and the DMA through the fall, according to the DMA.