Theoretical Approach to Polarization Effects in Semiconductors.- Polarization Induced Effects in GaN-based Heterostructures and Novel Sensors.- Lateral and Vertical Charge Transport in Polar Nitride Heterostructures.- Polarization Effects on Low-Field Transport & Mobility in III-V Nitride HEMTs.- Local Polarization Effects in Nitride Heterostructures and Devices.- Polarization in Wide Bandgap Semiconductors and their Characterization by Scanning Probe Microscopy.- Functionally Graded Polar Heterostuctures: New Materials for Multifunctional Devices.- Polarization in GaN Based Heterostructures and Heterojunction Field Effect Transistors (HFETs).- Effects of Polarization in Optoelectronic Quantum Structures.