INTETAIN stands for Intelligent Technologies for Interactive Entertainment. The fourth conference (INTETAIN 2011) was held in Genova, Italy, May 25-27, 2011. Previous conferences were held in Madonna di Campiglio (Italy), Playa del Carmen (Mexico), and Amsterdam (The Netherlands). The INTETAIN conferences intend to stimulate interaction among academic researchers and commercial developers of interactive entertainment systems. The conferences focus on the development of novel user-centered intelligent computational technologies and interactive applications for entertainment, being made possible through the use of a wide range of interactive device technologies (e.g., mobile and wearable devices, home entertainment centers, haptic devices, wall screen displays, information kiosks, holographic displays, fog screens, distributed smart sensors, and immersive displays) and media delivery infrastructures (e.g., multimedia networks, interactive radio, streaming technologies, DVB-T/M, ITV, P2P, satellite broadcasting, UMTS, Bluetooth, Broadband, and VoIP).