Following the mid-1980s discovery of fullerenes, their optical properties quickly drew a lot of attention as the intrinsically allowed electronic transitions did not seem to alone explain the complexities of their spectra. Even after more than three decades, there is still little knowledge of the intricate details of their absorption and emission spectra. The main issue with these carbon cages is the high density of electronic states in the energy range of interest. From an experimental standpoint, this means that high resolution spectra are needed to accurately distinguish the electronic and vibronic structure. On the other hand, such a high density of electronic states tests the limits of first-principle calculations, as the computational cost for precisely predicting electronic states quickly becomes prohibitive for systems as large as fullerenes.In this presentation, we will discuss the challenges and importance of including vibronic coupling in the Ab initio calculation of fullerenes' optical spectra. This is necessary in order to gain a reliable interpretation of their electronic spectra and make the most of spectroscopy to probe the electronic structure of fullerenes.