Smart email marketing engages users in their inbox with targeted offers that can be shared virally through email and social media to drive more leads and sales. It builds social sharing into emails through tools like in-email polls, quizzes, and shares. This allows social interactions to occur inside emails, on websites, and across social media and affiliate sites to optimize leads, sales, and conversions through cross-channel sharing and sales. The key is to plan for social interactions across all channels to increase engagement from emails, drive more users to the website, and boost social media engagement.