User research is a series of processes that aim at getting to know the user, understanding the business and providing information that is essential for the entire process of developing a product or service. We focus on users because they are the ones who will make use of the product or have the experience. Moreover, because we are not them. We may have knowledge on the matter but that does not suffice to develop and design a good system, product or service. Besides the user interviews, there are other steps in the process of creating a VUI. From creating a system persona, establishing the voice tone, deciding if building an avatar or no, to error handling and designing dialog flows. Developing a well-defined system personality is essential to guarantee a coherent user experience able to make users trust your system. The goal in creating a persona is nor fooling the users making them believe they are interacting with a human being, but only making the most of that communication system all users learnt first and know better: conversation.