After finishing my PhD in Physics at the University Complutense of Madrid in 1994, wtih a Thesis about propagation, scattering, reflection and transmission of Biot’s waves (ultrasonic waves in fluid-saturated porous solids), I joined the Centre for Ultrasonic Engineering (directed by Prof. Gordon Hayward) at the E&EE faculty of the University of Strathclyde in Glasgow, Scotland, to aply the concepts of ultrasound propagation in porous media to the desing and developement of matching layers for air-coupled piezoelectric transducers. In 1998 I get a tenure track position at the Insituto de Acústica of the Spanish National Research Council (CSIC) in Madrid. Since then, my work has been focused on i) the use of ultrasounds (bulk waves, Lamb waves, surface waves, etc.) to characterize complex materials, and, more recently, soft matter, biomaterials, vegetal tissues and cellular solids, ii) the desing and construction of air-coupled piezoelectric transducers, iii) novel applications of ultrasonic techniques in the field of NDT. From 2003 to 2007 I was the Chief of the Ultrasonic Department of the Institute of Acoustics (CSIC). At present I am a researcher at the Sensors and Ultrasonic Technologies Department of the recently created (2013) Physics and Information Technologies Insitute at CSIC in Madrid.