Look for SSL encryption, a security protocol that shields data as it travels through the internet from your customers’ accounts to your website, as well as between your website and the payment servers. Look for PCI compliance, a set of standards and protocols enforced by the payment card industry for any company that accepts private credit card data. Working with a PCI-compliant payment processor means that the processor takes full responsibility and liability for all card data storage. That said, SSL encryption and PCI compliance are the bare minimum for keeping your customers secure and stress free; the more advanced payment processors protect merchants from fraudulent parties by providing authentication to buyers and spotting fraud before you even fulfill an order.