In imperfect competitive markets rms have some market power, thus the practice of price discrimination is possible. In oligopolistic models, behaviour-based price discrimination is analyzed following two different approaches: the switching costs ap- proach and the brand preferences approach. A recent Ofcom s report makes a reminder to the practice of rms implementing retention strategies, as a way to discourage cus- tomers to change the current supplier offering to all customers who show an intention to switch a special price discount. The main objective of this Master Dissertation is to develop a theoretical model that analyzes the effects of retention strategies under the switching costs approach. After consumers have made their first-period consumption decisions and decide to change supplier in the second-period, they have to incur switching costs. It is a model that extends Chen (1997) by allowing rms to employ retention strategies. It is also a model based on Esteves and Rey (2010), that consider retention activity but under the brand preferences approach. The results, when compared to those obtained without retention strategies, suggest (i) a lower deadweight loss due the less inefficient switching; (ii) a lower firms profits; and (iii) a higher consumers surplus.