Multichannel marketing communications have multiple benefits, including a broader audience reach, multiple touch points to reach customers and greater amplification of your message. But the dangerous duo of spam and viruses that have eroded consumer trust in email marketing have now spread to mobile and social channels, as hackers and spammers become smarter about launching attacks on these channels. As a result, online marketers now face the challenge of wary customers who are skeptical of the messages they receive, regardless of medium. Companies must set themselves apart from fraudsters in order to build a relationship of customer trust across all channels -- as we would all hate to lose a valued customer over a bad search experience or misdirected mobile message, for example. The good news is, the traditional rules for building trust via email campaigns apply to social channels as well; the key is to ensure your messages are aligned across channels. Here we share three strategies to ensure your online marketing campaign tells a trustworthy story. 1. Email marketing is the foundation of trust-building. Email marketing campaigns are deemed trustworthy when a subscriber views them as something they are receiving by choice. Enter the transparent opt-in process.This means no prechecked box on the opt-in form, clear statements about content, format, and frequency -- and plain-language terms of service and privacy policy, among other key features. Email designand functionality are also important to recipients trying to determine whether your communications are spam. To ensure your emails get instant inbox recognition, include the brand, company, or newsletter name in the "from" field (never a person's name or email address) or the subject line, or both. Emails should also include relevant content that displays clearly, with or without images, in the email and the preview pane. Finally, emails should be free of blocked images, bad code and broken links. 2. Extending trust to mobile devices. Another way to build customer trust is to allow subscribers to choose the method in which they want to be contacted -- for example, email or SMS. Use the credibility you've earned with email to achieve results via mobile. Similar best practices apply, such as: