The video discusses how to measure the effectiveness of influencer marketing. While it is difficult to measure accurately, there are some things you can do. One is taking a baseline of direct traffic and looking for spikes during activity on organic channels. If the influencer is using a social channel, you can track the URL or look at the source. For e-commerce sites, you can look at landing pages or unique promo codes. Larger brands can use metrics such as share of voice or Google Trends.