Twitter is the network that grew the most in 2012 and the one preferred by companies for establishing links of trust with their target public. With over 200 million active users and 175 million tweets per day, it is the ideal space for capturing possible clients and attending to those who already are. This article, developed in the framework of research project EHU11/11 funded by the University of the Basque Country (UPV/EHU), analyses the presence and activities of the main Spanish companies on Twitter. Outstanding amongst its conclusions is the change of strategy by companies over the last two years. Attention to clients comes before corporate information or launching offers and promotions, but there has been an increase in emocional adve...