Deciphering the molecular complexity of cultural heritage objects is central to understand an artwork or a museum object, how it was created or how it has changed over time. Molecular information can place objects in time, in space and in context. It informs us on societal, cultural and economic aspects of the past communities. It plays also a central role in conservation and preservation strategies as well as authentication. This PhD work will use unexplored and multifaceted developments in analytical chemistry to decipher in situ chemistries of ancient proteins (i.e. networks, molecular assemblies and interactions). To achieve these aims, the PhD fellow will design, assess, and deploy the most advanced and next generation workflows based on high-resolution mass spectrometry, employing the latest technical developments, several which have never been applied to Cultural Heritage, involving omics methods (top down, bottom up), structural mass spectrometry (XLMS and HDXMS) and MS imaging (MALDI IMS). The developed workflows will be miniaturized; tailored to the study of very small sample amounts (trace analysis). A fundamental challenge is to bridge the gap between the information currently available, which is mainly based on individual classes of molecule independent of their matrices, with understanding “multi-component materials” that inherently have highly complex interactions. The PhD project will benefit from the exceptional environment of The Metropolitan Museum of Art, New York, through its collections, the direct link with experts of other disciplines (conservators, art historians, archaeologists) as well as the scientists at the MET.