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Hola Miguel, Your choice should be between .es or .net. The .net is considered one of the best Top Level Domains so that would be first choice if I were building the site in the US. The .es domain would be a very good choice for a country specific domain and pretty much act like a .com for the country of Spain. My thought would be still to use the .net if possible it is more universal and easier to transport into other languages which sounds like something you want to do. Your questions.. Should I try to position each page separately? Or just alternate using "arte terapia" and "arteterapia" throughout the site? Don't try and compete with yourself for identical (ish) terms. Pick the one term that is "correct" or used / accepted the most and optimize for it. You'll find the near identical term still sends you results. Should my priority now be to choose one of these (probably arteterapiabarcelona.es) and try to get some backlinks or use them all? It would make much more sense to pick a single domain and do the hard work it takes to bring it to the top of the SERP's the it would be to try and do it for 2 or more domains in the same industry and the same time. In short focus on 1 domain, that is plenty of work. Are.cat domains as powerful for people doing searches in catalonia region as .es for people doing searches in spain? I don't know the answer to this question. Should she use Adsense? Any good tutorial on how to calculate the cost of that¿ Adsense is free (adsense is adding other peoples ads to your site) Were you thinking of Adwords? This is will create ads for your site on other sites, and you can pay by cpc (cost per click) or by the amount of ads displayed. Google will further allow you to setup a daily budget so you can spend as little or as much as you like. Since this is a Google product there is tons of help available on Google help, or try Googleing "adwords tutorial 2012" for some videos. Well I hope that helps.