The question posed is: to which extent fully glazed buildings, especially those designed by famous architects claiming themselves as environment-concerned, are actually sustainable? This is not a minor question, given their role as model examples of the rising new culture of sustainable building design. The effectiveness of envelope technologies largely used - such as all-glazed curtain wall, and double skin - will be discussed in this seminar, taking into account luminous, thermal and acoustic comfort with its connection to energy use, on the basis of the most recent findings available in specialized literature.