The aim of this paper is to introduce, in a consistent manner, a holistic appraisal of how to address refurbishment of modernist buildings of the late 20th century. Special attention to those with early use of structural glass will be given. We will present key influence factors to make the right choices. The history of glass use, its importance to architectural expression and technical challenges, will be outlined to understand all the sensitivities engineers will require to tackle during the discovery phase of the project. Some of the early projects from the late 70’s 80’s and early 90’s are coming to the end of their intended design life. Strategic advice to deal with challenges like: condition assessment, use of latest technology, interpretation of results, statutory requirements currently in place; clients expectations, and principles of circular economy will be outlined. During our work on projects we also discovered a few technical challenges, which were predominantly related to the glass design rules of the past, use of material and risk associated with it. Availability and quality of the technical documentation as well as alterations and modifications which all projects underwent during their lifetime will be also discussed. Due to the aging of the building stock and ever stronger sustainability objectives, it is our sincere opinion that those types of projects will be a sizable portion of projects future generations of engineers will have to be able to address in methodical ways.