 In a lecture delivered in Trieste in the last year of his life, Bell discussed the prospects for a genuinely relativistic version of a dynamical collapse theory, and concluded that the difficulties encountered by Ghirardi, Grassi, and Pearle in producing a genuinely relativistic version of the Continuous Spontaneous Localization theory (CSL), a theory that would be “Lorentz invariant, not just for all practical purposes but deeply, in the sense of Einstein, eliminating entirely any privileged reference system from the theory” (2007, 2931), were “Second-Class Difficulties,” technical difficulties, and not deep conceptual ones. This seems to have been borne out by the construction of the fully relativistic collapse theories already mentioned.