**Acknowledgements**

The author would like to thank Giuseppe Solaro, Fabiana Calò, Claudio Dema, Francesco Casu, and Riccardo Lanari, who was the co-authors of the MinA and POSBAS algorithms, which have been summarized in this Chapter. The author is also grateful to Simone Guarino, Fernando Parisi, and Maria Consiglia Rasulo for their technical support. ENVISAT data were provided by the European Space Agency, ALOS-1 data we provided by JAXA within the project entitled "Advanced Interferometric SAR Techniques for Earth Observation at L-band" of the four Research Agreement for the Advanced Land Observing Satellite-2. The DEM of the investigated zones were acquired through the SRTM archive.
