ABSTRACT This paper presents research on the development history as well as on the materials and techniques of technical installations with gas discharge lamps, colloquially known as ‘neon’ systems, in the former German Democratic Republic (GDR). Taking into account changes in materials, design, and technology between the 1950s and the 1980s, the findings also form the basis for the practical art-technological examination and evaluation of the examples still in existence. The majority of these objects have disappeared since the 1990s; the remainder are still acutely endangered today, due to progress in lighting technology and the current highly invasive repair practices. In this paper, a systematic examination case study is presented and discussed for the first time. The Poliklinik lettering under consideration is located on the façade of today's Medical Centre in the Hanseatic city of Stralsund and dates back to the second half of the 1950s. After more than 60 years of exposure to the elements, it appeared as an authentically aged, completely original example of the object group. A substance-careful concept for in situ examination was developed that did not require the fragile structure to be dismantled. The concept presented here is generally applicable to other objects with gas discharge lamps.