Unlike SEO, SEM or Search Engine Marketing is a quick method of achieving short-term marketing goals. The success of this type of strategy depends on the time we manage to sustain the investment and the segmentation method used. Unlike campaigns that use SEO, in the case of SEM when we stop paying for our “costs per click” (PPC) campaigns, we stop appearing and the space is occupied by another advertiser. Let’s not forget that this is an auction system and whoever offers the highest bid appears above the next bid level. SEM campaigns are ideal for obtaining immediate objectives: to sell a stock of products, to communicate our brand, to create databases or to be discovered by a certain audience. But unlike SEO they are not sustainable over time unless investment remains constant. PPC campaigns can be carried out on almost all platforms that have a search engine result page: Google, Facebook, Instagram, Twitter, Linkedin, Youtube and Pinterest. However, the effectiveness of these campaigns will depend on three basic factors: a careful selection of our “buyer persona” at the beginning of the campaign; the selection of the network or networks where the ads will be shown; and a detailed creation of our “conversion funnels” to channel all users according to their interests. The effectiveness and returns on investment will take longer to achieve unless these three points are defined at the beginning of our online marketing campaign.