Electricity market reforms around the world have introduced wholesale competition, open transmission across jurisdictions and often changed the ownership structure of companies. This seminar starts by reviewing different international experiences (Nordic countries, United Kingdom, California and other US cases) and reviews the different electricity market features: energy market, capacity market, ancillary services market, financial market and transmission rights, among others. In order to approach electricity competition in a realistic manner, participants will take part in an online competitive electricity market simulation, where they will have to behave, in terms as electricity generation companies. They will have to make investment choices in various technologies and make price-quantity energy offers in a day-ahead spot market. Through this active learning experience, lessons are drown on competition, collusion, appropriate technologies and the importance of demand forecast. This seminar uses some theory, practical country experiences and an applied simulation to deepen participants’ understanding and management skills of the electricity sector.