Multivariate testing is a method of experimentation where you test multiple variations of an asset, like an email, to see which combination performs the best. This is in contrast to A/B testing, where only one element is changed at a time. Multivariate testing can be used to test things like headlines, CTAs, and even images. The goal is to find the combination of elements that results in the highest conversion rate. To do this, four versions of the email are created and sent out to a pool of subscribers. The version that gets the most clicks is considered the winner and is then used going forward. Multivariate testing can be a great way to optimize your marketing assets and ensure that they are performing as well as possible.