Speaking at Marketing Direct's Profiting from Green Policies conference, held in London on Friday 9 November, Smith also said that the top twenty users of direct mail needed to "engage further on green matters".
"Direct marketing will be very much more on the consumer's agenda in the future and as an industry, we have to respond to this," she said. "Not doing anything is not an option. I would like to see the recycle logo on every piece of direct mail as part of the Code of Practice but this has yet to be decided."
Smith said that agreement from DMA members was vital to improve direct marketing's impact on the environment, but admitted there were some members "who do not perceive the need for change."
Smith added that recycling direct mail is not about reducing volumes but about proving that paper-based marketing is more effective.
"Even the most beautifully designed piece of direct mail creates a piece of paper that goes into the stream of mail," she said. "We need to do something about landfill."