New techniques and methodologies in the spectroscopic characterization of zeolites provide new insights on the complexity of zeolitic materials. In particular, emerging IR and NMR techniques shed new lights on old problems such as acidity. New, rich and quantitative information can be gathered. In particular, the ability to work under the so-called operando conditions yields much valuable data to rationally design better catalysts or zeolite based materials. The work and inspiration of Eric Derouane are often at the core of this new knowledge. (c) 2009 Elsevier B.V. All rights reserved.