Here we advocate the use of single-dot electrical and optical spectroscopy, or combinations of both, to study subtle energetic and dynamic features of colloidal core (shell) nanocrystalline quantum dots. In ensemble experiments, these features are hidden because of inhomogeneous broadening. The remarked physics of confined electrons and excitons as revealed by single-dot spectroscopy often reflects a coupling – enhanced by confinement in the nanocrystal – with other excitations such as lattice phonons and other carriers. We philosophize on a comprehensive single-dot experiment on semiconductor quantum dots that would combine optical and electrical spectroscopy with complete atomic imaging of the investigated structure.