One of the top items on every B-to-B marketer's agenda these days is gathering permission from prospects and customers to email them news, offers and/or product updates. This process (also known as collecting opt-ins) can be time consuming and expensive. However, two marketers have told us old-fashioned trade shows are the best way to grow an email list.

Stephanie Bauer, Web Admin Manager for the wireless association CTIA, tested a pop-up box on the CTIA site as well as banners on other wireless industry sites to gather opt-ins for CTIA's daily ezine. However, she says trade shows were one of her best sources for new subscribers, "We collect cards at our booth at all the shows and quite a few attendees will sign up for the newsletter right there. We also added an offer to the registration form for CTIA shows so when they register they can opt-in." This tactic helped Bauer grow subscribers from 30,000 to 50,000 in just 12 months.

Erin Lade, Marketing Manager at Lessiter Publications has also had her greatest success gathering opt-ins at trade shows. Lade doubled the list for Lessiter's weekly email newsletter for no-till farmers at a single conference, "We stuck a list out on the table. A lot of conference attendees who weren't subscribers loved it." Hundreds signed up in just four days.

Quick warning: Want to follow in Bauer and Lade's footsteps? Make sure the attendees you sign up are well aware that they are subscribing to a newsletter. Simply adding all the cards from your fishbowl to your email list is an easy way to get accused of spamming people!