Nowadays most people know brands like Booking.com, Expedia and Airbnb. When someone wants to book an accommodation, they usually book through an intermediary, known as Online Travel Agency or OTA. However, it is not well-understood what is the true influence that OTAs have on hotels, the core strength of their business, nor is it known what the impacts are on consumers. This dissertation tries to define the scope of influence that they have over hotels’ booking channels and the impact on consumers. Since OTAs’ ramifications span the entire world, this paper only defines their influence in Belgium, so as to reduce the scope of this research. This academic paper starts with an analysis of the background of OTAs. Then gives an explanation of OTA business models, pros and cons and what can be expected in the future. The analysis of different types of OTA or related businesses offers an understanding as to how they impact consumers. Next, an overview of the hospitality industry in Belgium is provided with data from 2007 to 2017. Changes in legislation throughout the European Union which are relevant to the subject are explained and the impacts on hotels and OTAs are analysed. After that, a quantitative survey about Belgian consumers is presented, from the way they book accommodations to what services they expect. Lastly, qualitative interviews with hotel managers complete the study. They provide an understanding as to how OTAs influence hotels and how hotel managers cope with this relationship. ; Hoje em dia, marcas como Booking.com, Expedia e Airbnb são conhecidas por grande parte da população. Quando alguém pretende fazer uma reserva de acomodação, a tendência é optar por reservar através de um intermediário, sendo mais conhecido no léxico do turismo como Online Travel Agency ou OTA. No entanto, não é verdadeiramente percetível a influência que as OTAs exercem sobre os hotéis- que são a sua principal força, nem é conhecido os impactos nos consumidores. Esta tese académica pretende, assim, definir o âmbito de ...